Fix rare assertion failure which could occur due to pending interrupts

* fix assertion failure
```
22:57:36 64409 [PositionPlugin] FIXME-update-db Sniffing packet
22:57:36 64409 [PositionPlugin] Delivering rx packet (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0x0 Portnum=3 rxtime=1628895456 priority=10)
22:57:36 64409 [PositionPlugin] Forwarding to phone (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0x0 Portnum=3 rxtime=1628895456 priority=10)
22:57:36 64409 [PositionPlugin] Update DB node 0x85f4da1, rx_time=1628895456
22:57:36 64409 [PositionPlugin] Plugin routing considered
22:57:36 64409 [PositionPlugin] Add packet record (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0x0 Portnum=3 rxtime=1628895456 priority=10)
22:57:36 64409 [PositionPlugin] Expanding short PSK #1
22:57:36 64409 [PositionPlugin] Installing AES128 key!
22:57:36 64409 [PositionPlugin] enqueuing for send (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0xb1 encrypted rxtime=1628895456 priority=10)
22:57:36 64409 [PositionPlugin] (bw=125, sf=12, cr=4/8) packet symLen=32 ms, payloadSize=22, time 2596 ms
22:57:36 64409 [PositionPlugin] txGood=6,rxGood=10,rxBad=0
22:57:36 64409 [PositionPlugin] AirTime - Packet transmitted : 2596ms
22:57:36 64409 [RadioIf] assert failed src/mesh/RadioLibInterface.cpp: 240, void RadioLibInterface::handleReceiveInterrupt(), test=isReceiving
```

geeksville-private/TODO.md

@@ -2,24 +2,6 @@
 
 You probably don't care about this section - skip to the next one.
 
-
-
-* fix assertion failure 
-```
-22:57:36 64409 [PositionPlugin] FIXME-update-db Sniffing packet
-22:57:36 64409 [PositionPlugin] Delivering rx packet (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0x0 Portnum=3 rxtime=1628895456 priority=10)
-22:57:36 64409 [PositionPlugin] Forwarding to phone (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0x0 Portnum=3 rxtime=1628895456 priority=10)
-22:57:36 64409 [PositionPlugin] Update DB node 0x85f4da1, rx_time=1628895456
-22:57:36 64409 [PositionPlugin] Plugin routing considered
-22:57:36 64409 [PositionPlugin] Add packet record (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0x0 Portnum=3 rxtime=1628895456 priority=10)
-22:57:36 64409 [PositionPlugin] Expanding short PSK #1
-22:57:36 64409 [PositionPlugin] Installing AES128 key!
-22:57:36 64409 [PositionPlugin] enqueuing for send (id=0x5851f437 Fr0xa1 To0xff, WantAck0, HopLim3 Ch0xb1 encrypted rxtime=1628895456 priority=10)
-22:57:36 64409 [PositionPlugin] (bw=125, sf=12, cr=4/8) packet symLen=32 ms, payloadSize=22, time 2596 ms
-22:57:36 64409 [PositionPlugin] txGood=6,rxGood=10,rxBad=0
-22:57:36 64409 [PositionPlugin] AirTime - Packet transmitted : 2596ms
-22:57:36 64409 [RadioIf] assert failed src/mesh/RadioLibInterface.cpp: 240, void RadioLibInterface::handleReceiveInterrupt(), test=isReceiving
-```
 * send debug info 'in-band'
 * fix wifi connections for mqtt
 * usb lora dongle from pine64

src/concurrency/NotifiedWorkerThread.cpp

@@ -72,14 +72,21 @@ bool NotifiedWorkerThread::notifyLater(uint32_t delay, uint32_t v, bool overwrit
     return didIt;
 }
 
-int32_t NotifiedWorkerThread::runOnce()
+void NotifiedWorkerThread::checkNotification()
 {
     auto n = notification;
-    enabled = false;  // Only run once per notification
     notification = 0; // clear notification
     if (n) {
         onNotify(n);
     }
+}
+
+
+
+int32_t NotifiedWorkerThread::runOnce()
+{
+    enabled = false;  // Only run once per notification
+    checkNotification();
 
     return RUN_SAME;
 }

src/concurrency/NotifiedWorkerThread.h

@@ -38,8 +38,14 @@ class NotifiedWorkerThread : public OSThread
   protected:
     virtual void onNotify(uint32_t notification) = 0;
 
+    /// just calls checkNotification()
     virtual int32_t runOnce();
 
+    /// Sometimes we might want to check notifications independently of when our thread was getting woken up (i.e. if we are about to change
+    /// radio transmit/receive modes we want to handle any pending interrupts first).  You can call this method and if any notifications are currently
+    /// pending they will be handled immediately.
+    void checkNotification();
+
   private:
     /**
      * Notify this thread so it can run

src/mesh/SX1262Interface.cpp

@@ -146,6 +146,8 @@ void INTERRUPT_ATTR SX1262Interface::disableInterrupt()
 
 void SX1262Interface::setStandby()
 {
+    checkNotification(); // handle any pending interrupts before we force standby
+    
     int err = lora.standby();
     assert(err == ERR_NONE);