Fix NPE if CarrierConfigManager is not available

Fixes: 155147094
Fixes: 155819375
Test: m RunSettingsRoboTests ROBOTEST_FILTER=com.android.settings.network.telephony
Change-Id: Iecf3e385a88d18c7578eb520449f4042324e21f5
Merged-In: Iecf3e385a88d18c7578eb520449f4042324e21f5
1 file changed