Sort relocs output by ld -r

Sort relocs output by ld -r

bfd/
	PR 17666
	* elflink.c: Include bfd_stdint.h.
	(cmp_ext32l_r_offset, cmp_ext32b_r_offset,
	cmp_ext64l_r_offset, cmp_ext64b_r_offset): New functions.
	(elf_link_adjust_relocs): Sort relocs.  Free reloc hashes after
	sorting invalidates.
ld/testsuite/
	* ld-powerpc/vxworks-relax.rd: Update for reloc sorting.
	* ld-powerpc/vxworks-relax-2.rd: Likewise.
	* ld-sh/sh64/reldl32.rd: Likewise.
	* ld-sh/sh64/reldl64.rd: Likewise.