Separate VoLTE and VT configurations to enable devices/carriers to have VoLTE without VT.

Change-Id: I233b003af57a550f2f51b12213700ab0451039e5
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 80d33f4..98a1f05 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -6599,7 +6599,7 @@
          * Type: int (0 for false, 1 for true)
          * @hide
          */
-        public static final String VOLTE_VT_ENABLED = "volte_vt_enabled";
+        public static final String ENHANCED_4G_MODE_ENABLED = "volte_vt_enabled";
 
         /**
          * Settings to backup. This is here so that it's in the same place as the settings