PR ld/12845

	PR ld/12845
	* elf.c (_bfd_elf_init_private_section_data): Add an assertion
	that the output section has an allocated bfd_elf_section_data
	structure.
	* elfxx-mips.c (mips_elf_check_symbols): Do not create a stub for
	symbols in sections that have been removed by garbage collection.

	* emultempl/mipself.em (mips_add_stub_section): Do not add stubs
	for sections that have been removed by garbage collection.