* strings.c: Include config.h before bfd.h.
(file_off): New type.
(file_open): Define.
(print_strings): Use file_off instead of file_ptr. Print addresses
which don't fit into long correctly.
(get_char): Use file_off instead of file_ptr. Use getc_unlocked if
available.
(strings_file): Use file_off instead of file_ptr. Use file_open.
* configure.in: Check for getc_unlocked.
Check for fopen64 and whether _LARGEFILE64_SOURCE needs to
be defined for it.
* configure: Rebuilt.
* config.h.in: Rebuilt.