fix #4367 make USB power detection work correctly on seeed trackers (#4376)

for wio tracker 1110 and 1000-E and possibly other nrf52 boards.
The problem was that nrf52 power stuff wasn't generating regular
powerstatus notifications (because that code was guarded by a batteryLevel
check which was null for those boards).  So I've cleaned up the battery status stuff
a bit and we now have fewer special cases.
Tested on a 1000-E, tracker 1110 and a rak4631 board.

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

variants/tracker-t1000-e/variant.h

@@ -40,6 +40,9 @@ extern "C" {
 #define NUM_ANALOG_INPUTS (6)
 #define NUM_ANALOG_OUTPUTS (0)
 
+// Use the native nrf52 usb power detection
+#define NRF_APM
+
 #define PIN_3V3_EN (32 + 6)     // P1.6, Power to Sensors
 #define PIN_3V3_ACC_EN (32 + 7) // P1.7, Power to Acc
 
@@ -147,4 +150,4 @@ extern "C" {
  *        Arduino objects - C++ only
  *----------------------------------------------------------------------------*/
 
-#endif // _VARIANT_TRACKER_T1000_E_
+#endif // _VARIANT_TRACKER_T1000_E_