Add getAllowedNetworkTypesBitmap HAL API

Adds corresponding query API getAllowedNetworkTypesBitmap to
existing setAllowedNetworkTypeBitmap.

Test: atest
Bug: 171791177
Change-Id: Ib8f0075dda41d4876a14f7223a067e34626a4675
diff --git a/radio/1.6/IRadio.hal b/radio/1.6/IRadio.hal
index 2c8ac5e..4566558 100644
--- a/radio/1.6/IRadio.hal
+++ b/radio/1.6/IRadio.hal
@@ -327,12 +327,26 @@
      * @param serial Serial number of request.
      * @param networkTypeBitmap a 32-bit bearer bitmap of RadioAccessFamily
      *
-     * Response callbask is IRadioResponse.setNetworkTypeBitmapResponse()
+     * Response callback is IRadioResponse.setNetworkTypeBitmapResponse()
      */
     oneway setAllowedNetworkTypeBitmap(
             uint32_t serial, bitfield<RadioAccessFamily> networkTypeBitmap);
 
     /**
+     * Requests bitmap representing the currently allowed network types.
+     *
+     * Requests the bitmap set by the corresponding method
+     * setAllowedNetworkTypeBitmap, which sets a strict set of RATs for the
+     * radio to use. Differs from getPreferredNetworkType and getPreferredNetworkTypeBitmap
+     * in that those request *preferences*.
+     *
+     * @param serial Serial number of request.
+     *
+     * Response callback is IRadioResponse.getNetworkTypeBitmapResponse()
+     */
+    oneway getAllowedNetworkTypeBitmap(uint32_t serial);
+
+    /**
      * Control data throttling at modem.
      *   - DataThrottlingAction:NO_DATA_THROTTLING should clear any existing
      *     data throttling within the requested completion window.