[Patch, ARM] check value of --with-arch against arm-arches.def

[Terry Guo]

Hi There,

This patch intends to check value of --with-arch against the arm-arches.def,
rather than current solution that use hard coded things in config.gcc.
Tested with various values of --with-arch and it works. Is it ok to trunk?

BR,
Terry

2013-12-30  Terry Guo  <terry....@arm.com>

     * config.gcc (arm*-*-*): Check --with-arch against arm-arches.def.
diff --git a/gcc/config.gcc b/gcc/config.gcc
index 24dbaf9..7c4a0b9 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -3455,19 +3455,17 @@ case "${target}" in
                        fi
                done
 
-               case "$with_arch" in
-               "" \
-               | armv[23456] | armv2a | armv3m | armv4t | armv5t \
-               | armv5te | armv6j |armv6k | armv6z | armv6zk | armv6-m \
-               | armv7 | armv7-a | armv7-r | armv7-m | armv8-a \
-               | iwmmxt | ep9312)
-                       # OK
-                       ;;
-               *)
-                       echo "Unknown arch used in --with-arch=$with_arch" 1>&2
-                       exit 1
-                       ;;
-               esac
+               # See if it matches any of the entries in arm-arches.def
+               if [ x"$with_arch" = x ] \
+                   || grep "^ARM_ARCH(\"$with_arch\"," \
+                           ${srcdir}/config/arm/arm-arches.def \
+                           > /dev/null; then
+                 # OK
+                 true
+               else
+                 echo "Unknown arch used in --with-arch=$with_arch" 1>&2
+                 exit 1
+               fi
 
                case "$with_float" in
                "" \