rtmpproto: Send chunk size on the network channel

This makes sure that e.g. Adobe FME actually reacts to it. As long
as the value we've been sending is the default one (128), the bug
hasn't been noticed.
Signed-off-by: Martin Storsjö <martin@martin.st>

libavformat/rtmpproto.c

@@ -492,7 +492,7 @@ static int read_connect(URLContext *s, RTMPContext *rt)
         return ret;
 
     // Chunk size
-    if ((ret = ff_rtmp_packet_create(&pkt, RTMP_SYSTEM_CHANNEL,
+    if ((ret = ff_rtmp_packet_create(&pkt, RTMP_NETWORK_CHANNEL,
                                      RTMP_PT_CHUNK_SIZE, 0, 4)) < 0)
         return ret;