Free AVStream->info in chained muxers

This fixes memory leaks in the RTSP muxer and RTP hinting in the
mov muxer present since SVN rev 25418.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
(cherry picked from commit ce41c51b)

libavformat/movenchint.c

@@ -86,6 +86,7 @@ fail:
     }
     if (track->rtp_ctx && track->rtp_ctx->streams[0]) {
         av_metadata_free(&track->rtp_ctx->streams[0]->metadata);
+        av_free(track->rtp_ctx->streams[0]->info);
         av_free(track->rtp_ctx->streams[0]);
     }
     if (track->rtp_ctx) {
@@ -490,6 +491,7 @@ void ff_mov_close_hinting(MOVTrack *track) {
     }
     av_metadata_free(&rtp_ctx->streams[0]->metadata);
     av_metadata_free(&rtp_ctx->metadata);
+    av_free(rtp_ctx->streams[0]->info);
     av_free(rtp_ctx->streams[0]);
     av_freep(&rtp_ctx);
 }

libavformat/rtpenc_chain.c

@@ -70,6 +70,7 @@ AVFormatContext *ff_rtp_chain_mux_open(AVFormatContext *s, AVStream *st,
             url_close_dyn_buf(rtpctx->pb, &ptr);
             av_free(ptr);
         }
+        av_free(rtpctx->streams[0]->info);
         av_free(rtpctx->streams[0]);
         av_free(rtpctx);
         return NULL;

libavformat/rtsp.c

@@ -500,6 +500,7 @@ void ff_rtsp_undo_setup(AVFormatContext *s)
                 }
                 av_metadata_free(&rtpctx->streams[0]->metadata);
                 av_metadata_free(&rtpctx->metadata);
+                av_free(rtpctx->streams[0]->info);
                 av_free(rtpctx->streams[0]);
                 av_free(rtpctx);
             } else if (rt->transport == RTSP_TRANSPORT_RDT && CONFIG_RTPDEC)