plugin: Don't invoke LTO-wrapper

Don't invoke LTO-wrapper since the LTO wrapper approach is not only
slow but also unreliable.  For GCC 10 or newer, LDPT_ADD_SYMBOLS_V2
will be used.

bfd/

	* configure.ac (HAVE_EXECUTABLE_SUFFIX): Removed.
	(EXECUTABLE_SUFFIX): Likewise.
	* config.in: Regenerated.
	* configure: Likewise.
	* plugin.c (bfd_plugin_close_and_cleanup): Defined as
	_bfd_generic_close_and_cleanup.
	(plugin_list_entry): Remove resolution_file, resolution_option,
	real_bfd, real_nsyms, real_syms, lto_nsyms, lto_syms, gcc,
	lto_wrapper, gcc_env and initialized,
	(need_lto_wrapper_p): Removed.
	(get_lto_wrapper): Likewise.
	(setup_lto_wrapper_env): Likewise.
	(register_all_symbols_read): Likewise.
	(egister_cleanup): Likewise.
	(get_symbols): Likewise.
	(add_input_file): Likewise.
	(bfd_plugin_set_program_name): Remove need_lto_wrapper.
	(add_symbols): Updated.
	(try_claim): Likewise.
	(try_load_plugin): Likewise.
	(bfd_plugin_canonicalize_symtab): Likewise.
	* plugin.h (bfd_plugin_set_program_name): Remove int argument.
	(plugin_data_struct): Remove real_bfd, real_nsyms and real_syms.

binutils/

	* ar.c (main): Update bfd_plugin_set_program_name call.
	* nm.c (main): Likewise.

ld/

	* testsuite/ld-plugin/lto.exp (lto_link_tests): Run PR ld/25355
	test only for GCC 10 or newer.