Re #1443 - Reverting back d675ab1578 with some improvements:

* when telemetry is not streaming all logical switches that involve telemetry value evaluate to FALSE (same as before the change in above commit)
* the duration and delay processing is now enabled for such logical switches (new functionality that was not present before above commit)

radio/src/switches.cpp

@@ -242,8 +242,8 @@ bool getLogicalSwitch(uint8_t idx)
       // Telemetry
       if (v1 >= MIXSRC_FIRST_TELEM) {
         if ((!TELEMETRY_STREAMING() && v1 >= MIXSRC_FIRST_TELEM+TELEM_FIRST_STREAMED_VALUE-1) || IS_FAI_FORBIDDEN(v1-1)) {
-          x = 0;  //replace actual value with zero and continue processing (needed for duraton and delay)
-          //we could also return actual stored values (except when FAI FORBIDDEN, then we would return 0)
+          result = false;
+          goto DurationAndDelayProcessing;
         }
 
         y = convertLswTelemValue(ls);
@@ -334,6 +334,10 @@ bool getLogicalSwitch(uint8_t idx)
     }
   }
 
+#if defined(FRSKY)
+DurationAndDelayProcessing:
+#endif
+
 #if defined(CPUARM)
     if (ls->delay || ls->duration) {
       LogicalSwitchContext &context = lswFm[mixerCurrentFlightMode].lsw[idx];