feat: Support for ext. Multiplex MLink JR type module (#3352)

* introducing external MLink module telemetry as module PPM subtype

* implemented fix for sensor discovery display not showing all detected sensors (is in separate PR too)

implemented PPM subtypes in Companion

* add PPM subtype to model printer

finalize subtypes for PPM in Companion

* added logic to try to use HW UART with inverters turned off first (e.g. NV14), then, if not successfull use soft serial inverted (== uninverted data due to HW inverters on PCB)

changed start bit detection IRQ priority from 5 to the previous 0 (also in separate PR)

* extended telemetry timeout to 2s due to slow Mlink RSSI update rate

* changed the "NOTLM" sub-type texts to:

- "No Telem" for 128x64 (this is the max numbers of characters it can take)
- "No Telemetry" everything else including Companion

* Companion:

- lower case 1st charachter on PpmSubTypeStrings to ppmSubTypeStrings
- added telemetry hooks for ppmSubTypeStrings stringx

* simplified serial port initialization for MLink telemetry

* editorial change: corrected obsolete comment

companion/src/modelprinter.cpp

@@ -205,6 +205,8 @@ QString ModelPrinter::printModule(int idx)
   else {
     str << printLabelValue(tr("Protocol"), ModuleData::protocolToString(module.protocol));
     if (module.protocol) {
+      if (module.protocol == PULSES_PPM)
+        str << printLabelValue(tr("Sub Type"), module.subTypeToString());
       str << printLabelValue(tr("Channels"), QString("%1-%2").arg(module.channelsStart + 1).arg(module.channelsStart + module.channelsCount));
       if (module.protocol == PULSES_PPM || module.protocol == PULSES_SBUS) {
         str << printLabelValue(tr("Frame length"), QString("%1ms").arg(printPPMFrameLength(module.ppm.frameLength)));