PR29390, DW_CFA_AARCH64_negate_ra_state vs. DW_CFA_GNU_window_save

	PR 29390
binutils/
	* dwarf.c (is_aarch64, DW_CFA_GNU_window_save_name): New.
	(display_debug_frames): Use them.
	(init_dwarf_regnames_aarch64): Set is_aarch64.
	(init_dwarf_regnames_by_elf_machine_code): Clear is_aarch64.
	(init_dwarf_regnames_by_bfd_arch_and_mach): Likewise.
gas/
	* testsuite/gas/aarch64/pac_ab_key.d: Adjust expected output.
	* testsuite/gas/aarch64/pac_negate_ra_state.d: Likewise.