Turn off RTT if a carrier doesn't support it am: b209db8d03

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/opt/net/ims/+/12120134

Change-Id: I9852ff878ba675e8cc9bff0d828e9cc1cb1c70ed
diff --git a/src/java/com/android/ims/ImsManager.java b/src/java/com/android/ims/ImsManager.java
index f943c96..9a436c3 100644
--- a/src/java/com/android/ims/ImsManager.java
+++ b/src/java/com/android/ims/ImsManager.java
@@ -2077,6 +2077,8 @@
 
         if (isCarrierSupported) {
             setRttConfig(shouldImsRttBeOn);
+        } else {
+            setRttConfig(false);
         }
         return isCarrierSupported && shouldImsRttBeOn;
     }