Update airplane mode pref key so it's sliceable.

Bug: 110403709
Test: rebuild slice db
Change-Id: I16e13ec67705754fc55d8c797f94e407f617722c
diff --git a/res/xml/network_and_internet.xml b/res/xml/network_and_internet.xml
index 6eda0b0..0d130e0 100644
--- a/res/xml/network_and_internet.xml
+++ b/res/xml/network_and_internet.xml
@@ -68,7 +68,7 @@
         settings:useAdminDisabledSummary="true" />
 
     <com.android.settingslib.RestrictedSwitchPreference
-        android:key="airplane_mode"
+        android:key="toggle_airplane"
         android:title="@string/airplane_mode"
         android:icon="@drawable/ic_airplanemode_active"
         android:disableDependentsState="true"