libiberty: sync with gcc

This imports the following commits from GCC as of r15-5375-gbeec291225be9b:
	94bea5dd6c9a libiberity: ANSIfy test-demangle.c
	aa84020b2edb libiberty: Fix comment typos
	c1b2100e736c libiberty: Restore build with CP_DEMANGLE_DEBUG defined
	bb8dd0980b39 libiberty: Fix up > 64K section handling in simple_object_elf_copy_lto_debug_section [PR116614]

Approved-By: Tom Tromey <tom@tromey.com>
5 files changed