fix: don't wake up after USB connect (#644)

## Summary

* fixes problem that if short power button press is enabled, connecting
device to usb leads to waking up

lib/hal/HalGPIO.h

@@ -47,8 +47,9 @@ class HalGPIO {
   // Check if USB is connected
   bool isUsbConnected() const;
 
-  // Check if wakeup was caused by power button press
-  bool isWakeupByPowerButton() const;
+  enum class WakeupReason { PowerButton, AfterFlash, AfterUSBPower, Other };
+
+  WakeupReason getWakeupReason() const;
 
   // Button indices
   static constexpr uint8_t BTN_BACK = 0;