Remove bfd ELF_RELROPAGESIZE

Remove bfd ELF_RELROPAGESIZE

Now that ld properly aligns the end of the relro segment, the hack to
make relro work on powerpc can disappear.

bfd/
	* bfd.c (bfd_emul_get_commonpagesize): Remove relro param.
	Don't return bed->relropagesize.
	* elf-bfd.h (struct elf_backend_data): Remove relropagesize.
	* elfxx-target.h (ELF_RELROPAGESIZE): Remove.
	* elf32-ppc.c (ELF_RELROPAGESIZE): Don't define.
	* elf64-ppc.c: Likewise.
	* bfd-in2.h: Regenerate.
ld/
	* ldemul.c (after_parse_default): Adjust
	bfd_emul_get_commonpagesize call.