Allow really large fortran array bounds: fortran type/value printers

This is the fortran part of the patch, including tests, which
are essentially unchanged from Siddhesh's original 2012 submission:

  https://sourceware.org/ml/gdb-patches/2012-08/msg00562.html

There is, however, one large departure.  In the above thread,
Jan pointed out problems with GCC debuginfo for -m32 builds
(filed usptream as gcc/54934).  After investigating the issue,
I am dropping the hand-tweaked assembler source file to workaround
this case.

While I would normally do something to accommodate this, in
this case, given the ubiquity of 64-bit systems today (where
the tests pass) and the apparent lack of urgency on the compiler
side (by users), I don't think the additional complexity and
maintenance costs are worth it. It will be very routinely tested
on 64-bit systems. [For example, at Red Hat, we always
test -m64 and -m32 configurations for all GDB releases.]

gdb/ChangeLog:

	From Siddhesh Poyarekar:
	* f-lang.h (f77_get_upperbound): Return LONGEST.
	(f77_get_lowerbound): Likewise.
	* f-typeprint.c (f_type_print_varspec_suffix): Expand
	UPPER_BOUND and LOWER_BOUND to LONGEST.  Use plongest to format
	print them.
	(f_type_print_base): Expand UPPER_BOUND to LONGEST.  Use
	plongest to format print it.
	* f-valprint.c (f77_get_lowerbound): Return LONGEST.
	(f77_get_upperbound): Likewise.
	(f77_get_dynamic_length_of_aggregate): Expand UPPER_BOUND,
	LOWER_BOUND to LONGEST.
	(f77_create_arrayprint_offset_tbl): Likewise.

gdb/testsuite/ChangeLog:

	* gdb.fortran/array-bounds.exp: New file.
	* gdb.fortran/array-bounds.f90: New file.

gdb/f-lang.h

@@ -50,9 +50,9 @@ struct common_block
   struct symbol *contents[1];
 };
 
-extern int f77_get_upperbound (struct type *);
+extern LONGEST f77_get_upperbound (struct type *);
 
-extern int f77_get_lowerbound (struct type *);
+extern LONGEST f77_get_lowerbound (struct type *);
 
 extern void f77_get_dynamic_array_length (struct type *);