Do exit if test for hostlongbits on ppc64 fails

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4940 c046a42c-6fe2-441c-8c8c-71466251a162

configure

@@ -648,10 +648,11 @@ EOF
         case $? in
             4) hostlongbits="32";;
             8) hostlongbits="64";;
-            *) echo "Couldn't determine bits per long value";;
+            *) echo "Couldn't determine bits per long value"; exit 1;;
         esac
     else
         echo hostlongbits test failed
+        exit 1
     fi
 fi