Now yields after MPEG_NEED_DATA

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@1118 a1c6a512-1295-4272-9138-f99709370657

firmware/mpeg.c

@@ -457,6 +457,7 @@ static void mpeg_thread(void)
                             queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
                         }
                     }
+                    yield(); /* To be safe */
                 }
                 break;
         }