Extend light-greylist of some TelephonyManager APIs until Q.

The reasonable replacement for these APIs is
ImsMmtelManager#isAvailable(int, int); however that class is a system
API.  Given how late we are in the release cycle,  can make
ImsMmtelManager public R and leave these greylisted for now.

Test: Manual
Bug: 128696104
Change-Id: I64fa9e079e26ba16ff9ace098091c4094e9a7b33

telephony/java/android/telephony/TelephonyManager.java

@@ -8107,7 +8107,7 @@ public class TelephonyManager {
      * @see SubscriptionManager#getDefaultSubscriptionId()
      * @hide
      */
-    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
+    @UnsupportedAppUsage
     public boolean isVolteAvailable() {
         try {
             return getITelephony().isAvailable(getSubId(),
@@ -8126,7 +8126,7 @@ public class TelephonyManager {
      * @return true if VT is available, or false if it is unavailable or unknown.
      * @hide
      */
-    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
+    @UnsupportedAppUsage
     public boolean isVideoTelephonyAvailable() {
         try {
             return getITelephony().isVideoTelephonyAvailable(getSubId());
@@ -8141,7 +8141,7 @@ public class TelephonyManager {
      * @return true if VoWiFi is available, or false if it is unavailable or unknown.
      * @hide
      */
-    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P)
+    @UnsupportedAppUsage
     public boolean isWifiCallingAvailable() {
        try {
            return getITelephony().isWifiCallingAvailable(getSubId());