Get rid of unused data_runloop_osd_msg

runloop.c

@@ -1435,9 +1435,3 @@ end:
 
    return 0;
 }
-
-void data_runloop_osd_msg(const char *msg, size_t len)
-{
-   runloop_msg_queue_push(msg, 1, 10, true);
-}
-

tasks/tasks.h

@@ -144,8 +144,6 @@ bool rarch_task_push_overlay_load_default(
         rarch_task_callback_t cb, void *user_data);
 #endif
     
-void data_runloop_osd_msg(const char *s, size_t len);
-
 int find_first_data_track(const char* cue_path,
       int32_t* offset, char* track_path, size_t max_len);