configure: update tms470 detection for latest version

v5.0 of the TI ARM compiler changes the version string.
This updates the detection to check for both the old and
the new strings.
Signed-off-by: Mans Rullgard <mans@mansr.com>

configure

@@ -2275,7 +2275,7 @@ probe_cc(){
         _depflags='-MMD'
         _cflags_speed='-O3'
         _cflags_size='-Os'
-    elif $_cc -version 2>/dev/null | grep -q TMS470; then
+    elif $_cc -version 2>/dev/null | grep -Eq 'TMS470|TI ARM'; then
         _type=tms470
         _ident=$($_cc -version | head -n1 | tr -s ' ')
         _flags='--gcc --abi=eabi -me'