[Settings] Fix crash when no SIM

Airplane mode enabler exception under the condition of
no active subscription. This is due to incorrect null pointer
checking within source code.

Bug: 145830780
Test: manual
Change-Id: I47cb4d82b7b99b4c34270023cd58f479347477da

src/com/android/settings/AirplaneModeEnabler.java

@@ -97,7 +97,7 @@ public class AirplaneModeEnabler extends GlobalSettingsChangeListener {
         mServiceStateListeners.add(new ServiceStateListener(mTelephonyManager,
                 SubscriptionManager.INVALID_SUBSCRIPTION_ID, this));
 
-        if (subInfoList == null) {
+        if (subInfoList != null) {
             for (SubscriptionInfo subInfo : subInfoList) {
                 mServiceStateListeners.add(new ServiceStateListener(mTelephonyManager,
                         subInfo.getSubscriptionId(), this));