Revert "Revert "Update GNSS Batching to use new GnssLocation with elapsed realtime (HAL)""

This reverts commit b3721a68f273c305ea8e151cd3a8c192605370fc.

Reason for revert: 
It appears that the build includes ag/6721678 but not ag/6762021 even though they both were submitted together. Hence the build errors.

Change-Id: I4e58b29239d291ae3621b90e4507de8eb8838298
diff --git a/gnss/2.0/IGnss.hal b/gnss/2.0/IGnss.hal
index ba757d7..f19f8d0 100644
--- a/gnss/2.0/IGnss.hal
+++ b/gnss/2.0/IGnss.hal
@@ -27,6 +27,7 @@
 import IGnssMeasurement;
 import IAGnss;
 import IAGnssRil;
+import IGnssBatching;
 
 /**
  * Represents the standard GNSS (Global Navigation Satellite System) interface.
@@ -105,6 +106,13 @@
     getExtensionVisibilityControl() generates (IGnssVisibilityControl visibilityControlIface);
 
     /**
+     * This method returns the IGnssBatching interface.
+     *
+     * @return batchingIface Handle to the IGnssBatching interface.
+     */
+    getExtensionGnssBatching_2_0() generates (IGnssBatching batchingIface);
+
+    /**
      * Injects current location from the best available location provider.
      *
      * Unlike injectLocation, this method may inject a recent GNSS location from the HAL