[Settings] Remove access of TelecomManager.from()

Replace TelecomManager.from() into public API access.

Bug: 146187127
Test: build pass
Change-Id: Id9fa32063a9a7ea5b9107315e50330fa5eca41b7
diff --git a/src/com/android/settings/network/telephony/MobileNetworkUtils.java b/src/com/android/settings/network/telephony/MobileNetworkUtils.java
index cd4489d..a08b0c2 100644
--- a/src/com/android/settings/network/telephony/MobileNetworkUtils.java
+++ b/src/com/android/settings/network/telephony/MobileNetworkUtils.java
@@ -133,7 +133,8 @@
      */
     public static boolean isWifiCallingEnabled(Context context, int subId) {
         final PhoneAccountHandle simCallManager =
-                TelecomManager.from(context).getSimCallManagerForSubscription(subId);
+                context.getSystemService(TelecomManager.class)
+                       .getSimCallManagerForSubscription(subId);
         final int phoneId = SubscriptionManager.getSlotIndex(subId);
 
         boolean isWifiCallingEnabled;