libvo-aacenc: Fix assignments in if()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/libvo-aacenc.c

@@ -157,7 +157,7 @@ static int aac_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
             samples = (VO_PBYTE)frame->data[0];
         }
         /* add current frame to the queue */
-        if ((ret = ff_af_queue_add(&s->afq, frame) < 0))
+        if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
             return ret;
     }