Always free matching vector from bfd_check_format_matches
At least one place calling list_matching_formats failed to free the
"matching" vector from bfd_check_format_matches afterwards. Fix that
by calling free inside list_matching_formats.
binutils/
* bucomm.c (list_matching_formats): Free arg.
* addr2line.c (process_file): Adjust to suit.
* ar.c (open_inarch, ranlib_touch): Likewise.
* coffdump.c (main): Likewise.
* nm.c (display_archive, display_file): Likewise.
* objcopy.c (copy_file): Likewise.
* objdump.c (display_object_bfd): Likewise.
* size.c (display_bfd): Likewise.
* srconv.c (main): Likewise.
ld/
* ldlang.c (load_symbols): Free "matching".