Remove ALL_PSPACES

Remove ALL_PSPACES

This removes the ALL_PSPACES macro.  In this case it seemed cleanest
to change how program spaces are stored -- instead of using a linked
list, they are now stored in a std::vector.

gdb/ChangeLog
2020-05-08  Tom Tromey  <tom@tromey.com>

	* symtab.c (set_symbol_cache_size)
	(maintenance_print_symbol_cache, maintenance_flush_symbol_cache)
	(maintenance_print_symbol_cache_statistics): Update.
	* symmisc.c (print_symbol_bcache_statistics)
	(print_objfile_statistics, maintenance_print_objfiles)
	(maintenance_info_symtabs, maintenance_check_symtabs)
	(maintenance_expand_symtabs, maintenance_info_line_tables):
	Update.
	* symfile-debug.c (set_debug_symfile): Update.
	* source.c (forget_cached_source_info): Update.
	* python/python.c (gdbpy_progspaces): Update.
	* psymtab.c (maintenance_info_psymtabs): Update.
	* probe.c (parse_probes): Update.
	* linespec.c (iterate_over_all_matching_symtabs)
	(collect_symtabs_from_filename, search_minsyms_for_name): Update.
	* guile/scm-progspace.c (gdbscm_progspaces): Update.
	* exec.c (exec_target::close): Update.
	* ada-tasks.c (ada_tasks_new_objfile_observer): Update.
	* breakpoint.c (print_one_breakpoint_location)
	(create_longjmp_master_breakpoint)
	(create_std_terminate_master_breakpoint): Update.
	* progspace.c (program_spaces): Now a std::vector.
	(maybe_new_address_space): Update.
	(add_program_space): Remove.
	(program_space::program_space): Update.
	(remove_program_space): Update.
	(number_of_program_spaces): Remove.
	(print_program_space, update_address_spaces): Update.
	* progspace.h (program_spaces): Change type.
	(ALL_PSPACES): Remove.
	(number_of_program_spaces): Don't declare.
	(struct program_space) <next>: Remove.