Remove fsck.f2fs check for user-requested shutdown

The fsck.f2fs -p 2 command was observed to take
too much time. To improve the user experience,
this check is being removed from the shutdown process.

Bug: 416263922
Bug: 431893616
Test: UI shutdown
Change-Id: Ie1b1492910ea0291680739770a6b44e384890391
Signed-off-by: Randall Huang <huangrandall@google.com>