Don't create /dir in buildimage

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@6310 a1c6a512-1295-4272-9138-f99709370657

firmware/test/fat/test.sh

@@ -32,7 +32,6 @@ buildimage() {
     do
         echo apa > "$MOUNT/very $i long test filename so we can make sure they.work"
     done
-    mkdir $MOUNT/dir
     umount $MOUNT
 }