avcodec/cbs_h264: silence errors about end_of_seq nalus

[ffmpeg] AVBSFContext: Decomposition unimplemented for unit 4 (type 10).
Signed-off-by: Aman Gupta <aman@tmm1.net>

libavcodec/cbs_h2645.c

@@ -871,6 +871,9 @@ static int cbs_h264_read_nal_unit(CodedBitstreamContext *ctx,
         }
         break;
 
+    case H264_NAL_END_SEQUENCE:
+        return 0;
+
     default:
         return AVERROR(ENOSYS);
     }