IMS: Use the slot based ImsManager factory reset API.

Use the slot based factory reset API of ImsManager
to reset the IMS settings values for appropriate sub.

Test: Manual
Bug: 74412226
Change-Id: Iceabb225764ac01f0172142ef95e874ca93c061d

src/com/android/settings/ResetNetworkConfirm.java

@@ -105,7 +105,8 @@ public class ResetNetworkConfirm extends OptionsMenuFragment {
                 }
             }
 
-            ImsManager.factoryReset(context);
+            ImsManager.getInstance(context,
+                     SubscriptionManager.getPhoneId(mSubId)).factoryReset();
             restoreDefaultApn(context);
 
             Toast.makeText(context, R.string.reset_network_complete_toast, Toast.LENGTH_SHORT)