Fix the issue that uncrypt isn't called under quiescent mode

OTA fails on fugu under quiescent mode because the reboot reason changes
from "recovery-update" to "recovery-update,quiescent". The new reason
isn't checked in shutdown thread so that shutdown thread doesn't call
uncrypt properly before rebooting into recovery.

Bug: 62324707
Test: Recreated and fixed the "block.map" missing failure on fugu.

Change-Id: I110653cd64dbbdc71e89ead2197bf023a7c054e8