RX-fail probe: read the chip mode on every LR board

#11983 gives both LR drivers readChipMode() unconditionally now, so the
probe no longer needs the switch that used to compile it in.

Co-Authored-By: Jonathan Bennett <jbennett@incomsystems.biz>
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01REkPVFh6kvG4AZJ5A8AtM9

src/mesh/LR11x0Interface.h

@@ -71,11 +71,7 @@ template <class T> class LR11x0Interface : public RadioLibInterface
     {
         pktType = 0xEE;
         typeErr = lora.getPacketType(&pktType);
-#ifdef LR11X0_READ_CHIP_MODE
         mode = this->readChipMode();
-#else
-        mode = 0xEE; // not compiled in on this board
-#endif
         irq = lora.getIrqFlags();
         return true; // always report: a failed GetPacketType is the case of interest, not a reason to stay silent
     }

src/mesh/LR20x0Interface.h

@@ -78,11 +78,7 @@ template <class T> class LR20x0Interface : public RadioLibInterface
     {
         pktType = 0xEE;
         typeErr = lora.getPacketType(&pktType);
-#ifdef LR2021_READ_CHIP_MODE
         mode = this->readChipMode();
-#else
-        mode = 0xEE; // not compiled in on this board
-#endif
         irq = lora.getIrqFlags();
         return true; // always report: a failed GetPacketType is the case of interest, not a reason to stay silent
     }