SoapySDR support: output: tunable elements GUIs fixes

plugins/samplesink/soapysdroutput/soapysdroutputgui.cpp

@@ -54,6 +54,7 @@ SoapySDROutputGui::SoapySDROutputGui(DeviceUISet *deviceUISet, QWidget* parent)
     createAntennasControl(m_sampleSink->getAntennas());
     createRangesControl(&m_sampleRateGUI, m_sampleSink->getRateRanges(), "SR", "S/s");
     createRangesControl(&m_bandwidthGUI, m_sampleSink->getBandwidthRanges(), "BW", "Hz");
+    createTunableElementsControl(m_sampleSink->getTunableElements());
 
     if (m_sampleRateGUI) {
         connect(m_sampleRateGUI, SIGNAL(valueChanged(double)), this, SLOT(sampleRateChanged(double)));