rtpdec: Remove a woefully misplaced comment

The code below the comment does not at all relate to statistics,
and even if moved to the right place, the comment adds little
value.
Signed-off-by: Martin Storsjö <martin@martin.st>

libavformat/rtpdec.c

@@ -50,7 +50,6 @@ static RTPDynamicProtocolHandler opus_dynamic_handler = {
     .codec_id   = AV_CODEC_ID_OPUS,
 };
 
-/* statistics functions */
 static RTPDynamicProtocolHandler *rtp_first_dynamic_payload_handler = NULL;
 
 void ff_register_dynamic_payload_handler(RTPDynamicProtocolHandler *handler)