Fix missing log steps at 0.1s period (#1967)

fixed issued where log steps would be missed due to 10ms timer resolution
- simulator: allow for one get_tmr10ms() tick (10ms) deviation
- radio: switched to FreeRTOS software timer at user requested period

code cleanup
log.cpp: made variable lastLogTime static
log.cpp: deleted unused variable g_logError
functions.cpp, logs.cpp, sdcard.h: renamed variable logDelay to logDelay100ms to show it is scaled to 100ms increments

radio/src/main.cpp

@@ -473,6 +473,10 @@ void guiMain(event_t evt)
 }
 #endif
 
+#if !defined(SIMU)
+  void initLoggingTimer();
+#endif
+
 void perMain()
 {
   DEBUG_TIMER_START(debugTimerPerMain1);
@@ -481,7 +485,12 @@ void perMain()
 
   if (!usbPlugged() || (getSelectedUsbMode() == USB_UNSELECTED_MODE)) {
     checkEeprom();
-    logsWrite();
+    
+    #if !defined(SIMU)     // use FreeRTOS software timer if radio firmware
+      initLoggingTimer();  // initialize software timer for logging
+    #else
+      logsWrite();         // call logsWrite the old way for simu
+    #endif
   }
 
   handleUsbConnection();