Revert "graceful shutdown in microdroid"

This reverts commit 4759c21cc02e4f2d271c5a467deb14119acb8982.

This no longer is needed as the timeout is set via
ro.build.shutdown_timeout which doesn't have min value.

Bug: 419607474
Test: N/A
Flag: EXEMPT revert
Change-Id: I9c646249722b182edc1049bf3ed368c3ce5bb628
1 file changed