Call update engine to apply payload

Calling update engine to apply payload provided from boot_otas and
reboot on success. Updating different dialogues for 4k prompt.

Test: m Settings && adb install -r $ANDROID_PRODUCT_OUT/system_ext/priv-app/Settings/Settings.apk
Test: make RunSettingsRoboTests ROBOTEST_FILTER=Enable16kPagesPreferenceControllerTest
Bug: 295573133
Change-Id: Iab90a2c2fae5f6aefce95b2306db91c7b056d9f7