ffserver: Fix one of the codec parameter checks

This is probably what was originally intended; the codec pointers are all NULL.

Fix by Howard Chu, hyc at highlandsun dot com

Originally committed as revision 23295 to svn://svn.ffmpeg.org/ffmpeg/trunk

ffserver.c

@@ -3697,7 +3697,7 @@ static void build_feed_streams(void)
                             ccs = ss->codec;
 #define CHECK_CODEC(x)  (ccf->x != ccs->x)
 
-                            if (CHECK_CODEC(codec) || CHECK_CODEC(codec_type)) {
+                            if (CHECK_CODEC(codec_id) || CHECK_CODEC(codec_type)) {
                                 http_log("Codecs do not match for stream %d\n", i);
                                 matches = 0;
                             } else if (CHECK_CODEC(bit_rate) || CHECK_CODEC(flags)) {