Extract caption service descriptors in the PMT program info.

The caption service descriptors are placed there when we see them in the VCT but not in the PMT when recording.

mythtv/libs/libmythtv/avformatdecoder.cpp

@@ -1476,10 +1476,16 @@ void AvFormatDecoder::ScanATSCCaptionStreams(int av_index)
     if (!pmt.IsVideo(i, "dvb"))
         return;
 
-    const desc_list_t desc_list = MPEGDescriptor::ParseOnlyInclude(
+    desc_list_t desc_list = MPEGDescriptor::ParseOnlyInclude(
         pmt.StreamInfo(i), pmt.StreamInfoLength(i),
         DescriptorID::caption_service);
 
+    const desc_list_t desc_list2 = MPEGDescriptor::ParseOnlyInclude(
+        pmt.ProgramInfo(), pmt.ProgramInfoLength(),
+        DescriptorID::caption_service);
+
+    desc_list.insert(desc_list.end(), desc_list2.begin(), desc_list2.end());
+
     for (uint j = 0; j < desc_list.size(); j++)
     {
         const CaptionServiceDescriptor csd(desc_list[j]);