Add reason why userspace reboot shutdown sequence failed

Test: atest CtsUserspaceRebootHostSideTestCases
Bug: 154772075
Merged-In: I7e4674c474189b0185c020e3e066aea5678d7428
Change-Id: I7e4674c474189b0185c020e3e066aea5678d7428
(cherry picked from commit a4e83ad3d7147f1168c55d8da60304666221208d)
1 file changed