fix crash when connecting to SDR after opening RFE panel
fix crash when connecting to SDR after opening RFE panel

myriadrf/LimeSuite,myriadrf/LimeSuite,limemicro/lms7suite,limemicro/lms7suite,limemicro/lms7suite,myriadrf/LimeSuite,limemicro/lms7suite,limemicro/lms7suite,myriadrf/LimeSuite,myriadrf/LimeSuite