Use config.bfd to determine the default architecture and byte order.

Flush all BYTE_ORDER_DEFAULT macros from mips. Can rely on BFD's value.

gdb/configure.in

@@ -71,9 +71,22 @@ changequote(,)dnl
 
 . ${srcdir}/configure.tgt
 
+targ=${target} ; . ${srcdir}/../bfd/config.bfd
+
 dnl
 changequote([,])dnl
 
+dnl use BFD to determine the default architecture and byte order
+dnl (bfd_vec->byteorder provides the latter).
+targ=${target}
+. ${srcdir}/../bfd/config.bfd
+if test x"${targ_archs}" != x ; then
+    AC_DEFINE_UNQUOTED(DEFAULT_BFD_ARCH, ${targ_archs})
+fi
+if test x"${targ_defvec}" != x ; then
+    AC_DEFINE_UNQUOTED(DEFAULT_BFD_VEC, ${targ_defvec})
+fi
+
 AC_PROG_AWK
 AC_PROG_INSTALL
 AC_CHECK_TOOL(AR, ar)