* elflink.h (struct elf_final_link_info): Add shndxbuf_size.

	* elflink.h (struct elf_final_link_info): Add shndxbuf_size.
	(elf_bfd_final_link): Don't bother zeroing symtab_hdr fields.
	Set up a larger symshndxbuf, and write it out.  Free it on
	exit rather than freeing symbuf twice.  Correct section index
	on output section symbol loop.
	(elf_link_output_sym): Accumulate symbol extension section
	indices, reallocating symshndxbuf rather than writing it out.
	(elf_link_flush_output_syms): Don't flush symshndxbuf.
	* elf.c (assign_section_numbers): Init i_shdrp to all zero.
	Use bfd_zalloc to clear i_shdrp[0] too.