* common/gdb_vecs.c: New file, contents from utils.c.
* common/host-defs.h: New file, contents from defs.h.
* utils.h: New file, contents from defs.h.
* defs.h: Move all declarations of objects defined in utils.c
to utils.h (except QUIT() and related).
#include "utils.h", "host-defs.h".
* probe.h (probe_p): Move here from gdb_vecs.h.
* symfile.c: #include "probe.h" instead of "gdb_vecs.h".
* utils.c (free_char_ptr_vec): Moved to common/gdb_vecs.c.
(dirnames_to_char_ptr_vec_append, dirnames_to_char_ptr_vec): Ditto.
* Makefile.in (SFILES): Add common/gdb_vecs.c.
(HFILES_NO_SRCDIR): Add common/gdb_vecs.h, common/host-defs.h, utils.h.
(COMMON_OBS): Add gdb_vecs.o.
(gdb_vecs.o): New rule.