Remove parameter valaddr from la_val_print

Nowadays, we pass both val and return value of
value_contents_for_printing (val) to la_val_print.  The latter is
unnecessary.  This patch removes the second parameter of la_val_print,
and get valaddr in each language's implementation by calling
value_contents_for_printing.  Since value_contents_for_printing calls
value_fetch_lazy, I also make VAL non-const.

Note that
 - I don't clean up the valaddr usages in each language's routines,
 - I don't remove valaddr from apply_ext_lang_val_pretty_printer, and
   extension language ops apply_val_pretty_printer.

They can be done in followup patches.

gdb:

2016-11-08  Yao Qi  <yao.qi@linaro.org>

	* ada-lang.h (ada_val_print): Remove second parameter.  Remove
	const from "struct value *".
	* ada-valprint.c (print_field_values): Remove const from
	"struct value *".
	(val_print_packed_array_elements): Likewise.
	(print_variant_part): Likewise.
	(ada_val_print_string): Likewise.
	(ada_val_print_gnat_array): Likewise.
	(ada_val_print_ptr): Likewise.
	(ada_val_print_num): Likewise.
	(ada_val_print_enum): Likewise.
	(ada_val_print_flt): Likewise.
	(ada_val_print_union): Likewise.
	(ada_val_print_struct_union): Likewise.
	(ada_val_print_ref): Likewise.
	(ada_val_print_1): Remove second parameter.  Remove const from
	"struct value *".
	(ada_val_print): Likewise.
	* c-lang.h (c_val_print): Likewise.
	* c-valprint.c (c_val_print_array): Remove const from
	"struct value *".
	(c_val_print_ptr): Likewise.
	(c_val_print_struct): Likewise.
	(c_val_print_union): Likewise.
	(c_val_print_int): Likewise.
	(c_val_print_memberptr): Likewise.
	(c_val_print): Remove second parameter.  Remove const from
	"struct value *".  All callers updated.
	* cp-valprint.c (cp_print_value): Remove const from
	"struct value *".
	(cp_print_value_fields): Likewise.
	(c_val_print_value): Likewise.
	* d-lang.h (d_val_print): Remove second parameter.  Remove const
	from "struct value *".
	* d-valprint.c (dynamic_array_type): Likewise.
	(d_val_print): Likewise.
	* f-lang.h (f_val_print): Likewise.
	* f-valprint.c (f_val_print): Likewise.
	* go-lang.h (go_val_print): Likewise.
	* go-valprint.c (print_go_string): Likewise.
	(go_val_print): Likewise.
	* language.c (unk_lang_val_print): Likewise.
	* language.h (struct language_defn) <la_val_print>: Likewise.
	Update comments.
	(LA_VAL_PRINT): Remove.
	* m2-lang.h (m2_val_print): Remove const from
	"struct value *".
	* m2-valprint.c (m2_print_array_contents): Likewise.
	(m2_val_print): Likewise.
	* p-lang.h (pascal_val_print): Remove second parameter.  Remove
	const from "struct value *".
	(pascal_object_print_value_fields): Likewise.
	* p-valprint.c (pascal_val_print): Likewise.
	(pascal_object_print_value_fields): Likewise.
	(pascal_object_print_value): Likewise.
	* rust-lang.c (rust_get_disr_info): Likewise.
	(val_print_struct): Likewise.
	(rust_val_print): Likewise.
	* valprint.c (generic_val_print_array): Likewise.
	(generic_val_print_ptr): Likewise.
	(generic_val_print_memberptr): Likewise.
	(generic_val_print_ref): Likewise.
	(generic_val_print_enum): Likewise.
	(generic_val_print_flags): Likewise.
	(generic_val_print_func): Likewise.
	(generic_val_print_bool): Likewise.
	(generic_val_print_int): Likewise.
	(generic_val_print_char): Likewise.
	(generic_val_print_float): Likewise.
	(generic_val_print_decfloat): Likewise.
	(generic_val_print_complex): Likewise.
	(generic_val_print): Likewise.
	(val_print): Likewise.
	(common_val_print): Likewise.
	(val_print_type_code_flags): Likewise.
	(val_print_scalar_formatted): Likewise.
	(val_print_array_elements): Likewise.
	* valprint.h (val_print_array_elements): Update declaration.
	(val_print_scalar_formatted): Likewise.
	(generic_val_print): Likewise.
	* value.h (val_print): Likewise.

gdb/cp-valprint.c

@@ -82,7 +82,7 @@ static void cp_print_static_field (struct type *, struct value *,
 static void cp_print_value (struct type *, struct type *,
 			    const gdb_byte *, LONGEST,
 			    CORE_ADDR, struct ui_file *,
-			    int, const struct value *,
+			    int, struct value *,
 			    const struct value_print_options *,
 			    struct type **);
 
@@ -156,7 +156,7 @@ void
 cp_print_value_fields (struct type *type, struct type *real_type,
 		       const gdb_byte *valaddr, LONGEST offset,
 		       CORE_ADDR address, struct ui_file *stream,
-		       int recurse, const struct value *val,
+		       int recurse, struct value *val,
 		       const struct value_print_options *options,
 		       struct type **dont_print_vb,
 		       int dont_print_statmem)
@@ -353,7 +353,6 @@ cp_print_value_fields (struct type *type, struct type *real_type,
 
 		  opts.deref_ref = 0;
 		  val_print (TYPE_FIELD_TYPE (type, i),
-			     valaddr, 
 			     offset + TYPE_FIELD_BITPOS (type, i) / 8,
 			     address,
 			     stream, recurse + 1, val, &opts,
@@ -420,7 +419,7 @@ cp_print_value_fields_rtti (struct type *type,
 			    const gdb_byte *valaddr, LONGEST offset,
 			    CORE_ADDR address,
 			    struct ui_file *stream, int recurse,
-			    const struct value *val,
+			    struct value *val,
 			    const struct value_print_options *options,
 			    struct type **dont_print_vb, 
 			    int dont_print_statmem)
@@ -462,7 +461,7 @@ static void
 cp_print_value (struct type *type, struct type *real_type,
 		const gdb_byte *valaddr, LONGEST offset,
 		CORE_ADDR address, struct ui_file *stream,
-		int recurse, const struct value *val,
+		int recurse, struct value *val,
 		const struct value_print_options *options,
 		struct type **dont_print_vb)
 {
@@ -489,7 +488,7 @@ cp_print_value (struct type *type, struct type *real_type,
       struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
       const char *basename = TYPE_NAME (baseclass);
       const gdb_byte *base_valaddr = NULL;
-      const struct value *base_val = NULL;
+      struct value *base_val = NULL;
 
       if (BASETYPE_VIA_VIRTUAL (type, i))
 	{
@@ -708,7 +707,7 @@ cp_print_static_field (struct type *type,
 
   opts = *options;
   opts.deref_ref = 0;
-  val_print (type, value_contents_for_printing (val), 
+  val_print (type,
 	     value_embedded_offset (val),
 	     value_address (val),
 	     stream, recurse, val,