Properly set datalen field when doing PLC in codec_speex. (issue #9722 reported by mihai)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@64278 65c4cc65-6c06-0410-ace0-fbb531ad65f3

codecs/codec_speex.c

@@ -220,6 +220,7 @@ static int speextolin_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
 		}
 #endif
 		pvt->samples += tmp->framesize;
+		pvt->datalen += 2 * tmp->framesize; /* 2 bytes/sample */
 		return 0;
 	}