Always use RTP for 2nd camera stream

The ground station has a setting for raw/RTP video encapsulation, and
QOpenHD uses that setting to configure the video pipelines, however
there is no raw 2nd camera stream so the setting should be ignored for
that pipeline and always use RTP instead.

src/openhdvideostream.cpp

@@ -785,7 +785,7 @@ void OpenHDVideoStream::_start() {
     } else {
         qDebug() << "Listening on port" << m_video_port;
 
-        if (m_enable_rtp) {
+        if (m_enable_rtp || m_stream_type == StreamTypePiP) {
             s << QString("udpsrc port=%1 caps=\"application/x-rtp, media=(string)video, clock-rate=(int)90000, encoding-name=(string)H264\" timeout=1000000000 !").arg(m_video_port);
             s << "rtpjitterbuffer !";
             s << "rtph264depay ! ";