de-init bluetooth

src/nimble/NimbleBluetooth.cpp

@@ -112,6 +112,12 @@ void NimbleBluetooth::shutdown()
     NimBLEAdvertising *pAdvertising = NimBLEDevice::getAdvertising();
     pAdvertising->reset();
     pAdvertising->stop();
+
+#if defined(HELTEC_WIRELESS_PAPER) || defined(HELTEC_WIRELESS_PAPER_V1_0)
+    // Saving of ~1mA
+    // Probably applicable to other ESP32 boards - unverified
+    NimBLEDevice::deinit();
+#endif
 }
 
 bool NimbleBluetooth::isActive()