Add disable pSIM option in Settings

As we start disabling pSIM option in R, we check that if the feature is
supported, add the "Use SIM" toggle back to pSIM page.

Bug: 141018421
Test: manual test
Change-Id: I1af497ce5ede93f823825718b8136ff8ae0ab49c

src/com/android/settings/network/SubscriptionUtil.java

@@ -113,4 +113,11 @@ public class SubscriptionUtil {
         }
         return "";
     }
+
+    /**
+     * Whether Settings should show a "Use SIM" toggle in pSIM detailed page.
+     */
+    public static boolean showToggleForPhysicalSim(SubscriptionManager subMgr) {
+        return subMgr.canDisablePhysicalSubscription();
+    }
 }