fix(ble): Fix getPower return value

Author: lucasssvaz

libraries/BLE/src/BLEDevice.cpp

@@ -464,7 +464,7 @@ int BLEDevice::getPower(esp_ble_power_type_t powerType) {
     case ESP_PWR_LVL_N12: return -12;
     case ESP_PWR_LVL_N9:  return -9;
     case ESP_PWR_LVL_N6:  return -6;
-    case ESP_PWR_LVL_N3:  return -6;
+    case ESP_PWR_LVL_N3:  return -3;
     case ESP_PWR_LVL_N0:  return 0;
     case ESP_PWR_LVL_P3:  return 3;
     case ESP_PWR_LVL_P6:  return 6;