Get rid of VEC(static_tracepoint_marker_p)

This patch replaces VEC(static_tracepoint_marker_p) with std::vector,
and does some c++ification around that.  I thought a new overload of
hex2str was useful, so I added it as well as corresponding unit tests.
I also added an overload of ui_out::field_string that takes an
std::string directly.

gdb/ChangeLog:

	* tracepoint.h (struct static_tracepoint_marker): Initialize
	fields, define default constructor, move constructor and move
	assignment, disable the rest.
	<str_id, extra>: Make std::string.
	(release_static_tracepoint_marker): Remove.
	(free_current_marker): Remove.
	* tracepoint.c (free_current_marker): Remove.
	(parse_static_tracepoint_marker_definition): Adjust to
	std::string, use new hex2str overload.
	(release_static_tracepoint_marker): Remove.
	(print_one_static_tracepoint_marker): Get marker by reference
	and adjust to std::string.
	(info_static_tracepoint_markers_command): Adjust to std::vector
	changes
	* target.h (static_tracepoint_marker_p): Remove typedef.
	(DEF_VEC_P(static_tracepoint_marker_p)): Remove.
	(struct target_ops) <to_static_tracepoint_marker_at>: Return
	bool.
	<to_static_tracepoint_markers_by_strid>: Return std::vector.
	* target-debug.h
	(target_debug_print_VEC_static_tracepoint_marker_p_p): Remove.
	(target_debug_print_std_vector_static_tracepoint_marker): New.
	(target_debug_print_struct_static_tracepoint_marker_p): Rename
	to...
	(target_debug_print_static_tracepoint_marker_p): ... this.
	* target-delegates.c: Re-generate.
	* breakpoint.h (struct tracepoint) <static_trace_marker_id>:
	Make std::string.
	* breakpoint.c (init_breakpoint_sal): Adjust to std::string.
	(decode_static_tracepoint_spec): Adjust to std::vector.
	(tracepoint_print_one_detail): Adjust to std::string.
	(strace_marker_decode_location): Adjust to std::string.
	(update_static_tracepoint): Adjust to std::string, remove call
	to release_static_tracepoint_marker.
	* linux-nat.c (linux_child_static_tracepoint_markers_by_strid):
	Adjust to std::vector.
	* remote.c (remote_static_tracepoint_marker_at): Return bool.
	(remote_static_tracepoint_markers_by_strid): Adjust to
	std::vector.
	* common/rsp-low.h (hex2str): New overload with explicit count
	of bytes.
	* common/rsp-low.c (hex2str): New overload with explicit count
	of bytes.
	* unittests/rsp-low-selftests.c (test_hex2str): New function.
	(_initialize_rsp_low_selftests): Add test_hex2str test.
	* unittests/tracepoint-selftests.c
	(test_parse_static_tracepoint_marker_definition): Adjust to
	std::string.

gdb/target-delegates.c

@@ -3315,23 +3315,23 @@ debug_set_permissions (struct target_ops *self)
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
-static int
-delegate_static_tracepoint_marker_at (struct target_ops *self, CORE_ADDR arg1, struct static_tracepoint_marker *arg2)
+static bool
+delegate_static_tracepoint_marker_at (struct target_ops *self, CORE_ADDR arg1, static_tracepoint_marker *arg2)
 {
   self = self->beneath;
   return self->to_static_tracepoint_marker_at (self, arg1, arg2);
 }
 
-static int
-tdefault_static_tracepoint_marker_at (struct target_ops *self, CORE_ADDR arg1, struct static_tracepoint_marker *arg2)
+static bool
+tdefault_static_tracepoint_marker_at (struct target_ops *self, CORE_ADDR arg1, static_tracepoint_marker *arg2)
 {
-  return 0;
+  return false;
 }
 
-static int
-debug_static_tracepoint_marker_at (struct target_ops *self, CORE_ADDR arg1, struct static_tracepoint_marker *arg2)
+static bool
+debug_static_tracepoint_marker_at (struct target_ops *self, CORE_ADDR arg1, static_tracepoint_marker *arg2)
 {
-  int result;
+  bool result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->to_static_tracepoint_marker_at (...)\n", debug_target.to_shortname);
   result = debug_target.to_static_tracepoint_marker_at (&debug_target, arg1, arg2);
   fprintf_unfiltered (gdb_stdlog, "<- %s->to_static_tracepoint_marker_at (", debug_target.to_shortname);
@@ -3339,30 +3339,30 @@ debug_static_tracepoint_marker_at (struct target_ops *self, CORE_ADDR arg1, stru
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_CORE_ADDR (arg1);
   fputs_unfiltered (", ", gdb_stdlog);
-  target_debug_print_struct_static_tracepoint_marker_p (arg2);
+  target_debug_print_static_tracepoint_marker_p (arg2);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_int (result);
+  target_debug_print_bool (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }
 
-static VEC(static_tracepoint_marker_p) *
+static std::vector<static_tracepoint_marker>
 delegate_static_tracepoint_markers_by_strid (struct target_ops *self, const char *arg1)
 {
   self = self->beneath;
   return self->to_static_tracepoint_markers_by_strid (self, arg1);
 }
 
-static VEC(static_tracepoint_marker_p) *
+static std::vector<static_tracepoint_marker>
 tdefault_static_tracepoint_markers_by_strid (struct target_ops *self, const char *arg1)
 {
   tcomplain ();
 }
 
-static VEC(static_tracepoint_marker_p) *
+static std::vector<static_tracepoint_marker>
 debug_static_tracepoint_markers_by_strid (struct target_ops *self, const char *arg1)
 {
-  VEC(static_tracepoint_marker_p) * result;
+  std::vector<static_tracepoint_marker> result;
   fprintf_unfiltered (gdb_stdlog, "-> %s->to_static_tracepoint_markers_by_strid (...)\n", debug_target.to_shortname);
   result = debug_target.to_static_tracepoint_markers_by_strid (&debug_target, arg1);
   fprintf_unfiltered (gdb_stdlog, "<- %s->to_static_tracepoint_markers_by_strid (", debug_target.to_shortname);
@@ -3370,7 +3370,7 @@ debug_static_tracepoint_markers_by_strid (struct target_ops *self, const char *a
   fputs_unfiltered (", ", gdb_stdlog);
   target_debug_print_const_char_p (arg1);
   fputs_unfiltered (") = ", gdb_stdlog);
-  target_debug_print_VEC_static_tracepoint_marker_p_p (result);
+  target_debug_print_std_vector_static_tracepoint_marker (result);
   fputs_unfiltered ("\n", gdb_stdlog);
   return result;
 }