avplay: Don't call avio_set_interrupt_cb(NULL)

Since we don't use avio_set_interrupt_cb for interrupt callbacks,
we don't need to call it to reset the interrupt cb either.

This avoids a warning about use of deprecated functions.
Signed-off-by: Martin Storsjö <martin@martin.st>

avplay.c

@@ -2599,7 +2599,6 @@ static int decode_thread(void *arg)
     if (is->ic) {
         avformat_close_input(&is->ic);
     }
-    avio_set_interrupt_cb(NULL);
 
     if (ret != 0) {
         SDL_Event event;