Disable partition verification when device boots on snapshot

No need partition verification when device boots on snapshot without
slot switch.

This also saves couple of seconds of boot time.

Bug: 299011882
Test: Boot device on snapshot, OTA on Pixel
Change-Id: I5b781de7e0f745bbfe9646f88ca912139b2d853e
Signed-off-by: Akilesh Kailash <akailash@google.com>