don't check for string.h or strings.h

don't check for string.h or strings.h

Now that we are using the gnulib string.h module, we don't need to
check for string.h or strings.h.  This removes the last few checks
from the source and from the configure scripts.

2013-11-18  Tom Tromey  <tromey@redhat.com>

	* configure: Rebuild.
	* common/common.m4 (GDB_AC_COMMON): Don't check for string.h or
	strings.h.

2013-11-18  Tom Tromey  <tromey@redhat.com>

	* server.h: Don't check HAVE_STRING_H.
	* gdbreplay.c: Don't check HAVE_STRING_H.
	* configure: Rebuild.