* elflink.c (elf_link_input_bfd): Provide a file symbol for
each input file with local syms, if the input lacks such.
(bfd_elf_final_link): Add a file symbol to mark end of locals
for which we can associate with input files.
(struct elf_final_link_info): Add filesym_count field.
(struct elf_outext_info): Add need_second_pass and second_pass.
(elf_link_output_extsym): Detect symbols defined in the output
file, emit them on second pass over locals.
ld/testsuite/
Update to suit added STT_FILE symbols.