x86: Add -z isa-level-report=[none|all|needed|used]

Add -z isa-level-report=[none|all|needed|used] to the x86 ELF linker to
report needed and used x86-64 ISA levels.

bfd/

	PR ld/31868
	* elf-linker-x86.h (elf_x86_isa_level_report): New.
	(elf_linker_x86_params): Add isa_level_report.
	* elfxx-x86.c (report_isa_level): New.
	(_bfd_x86_elf_link_setup_gnu_properties): Check
	-z isa-level-report=[none|all|needed|used] to report needed and
	used x86-64 ISA level.

ld/

	PR ld/31868
	* NEWS: Mention -z isa-level-report=[none|all|needed|used].
	* ld.texi: Document -z isa-level-report=[none|all|needed|used].
	* emulparams/elf32_x86_64.sh: Source x86-64-level-report.sh.
	* emulparams/elf_i386.sh: Likewise.
	* emulparams/elf_x86_64.sh: Likewise.
	* emulparams/x86-64-level-report.sh: New file.
	* testsuite/ld-i386/pr31868a.d: Likewise.
	* testsuite/ld-i386/pr31868b.d: Likewise.
	* testsuite/ld-i386/pr31868c.d: Likewise.
	* testsuite/ld-x86-64/pr31868a-x32.d: Likewise.
	* testsuite/ld-x86-64/pr31868a.d: Likewise.
	* testsuite/ld-x86-64/pr31868a.l: Likewise.
	* testsuite/ld-x86-64/pr31868a.s: Likewise.
	* testsuite/ld-x86-64/pr31868b-x32.d: Likewise.
	* testsuite/ld-x86-64/pr31868b.d: Likewise.
	* testsuite/ld-x86-64/pr31868b.l: Likewise.
	* testsuite/ld-x86-64/pr31868b.s: Likewise.
	* testsuite/ld-x86-64/pr31868c-x32.d: Likewise.
	* testsuite/ld-x86-64/pr31868c.d: Likewise.
	* testsuite/ld-x86-64/pr31868c.l: Likewise.
	* testsuite/ld-i386/i386.exp: Run PR ld/31868 tests.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>