[minfs] Make fsck print the state of clean flag for better debugging

This change makes fsck print the state of clean flag for better debugging to help with debugging
in future crashes and being able to quickly eyeball in logs the state of a
system (whether it was unmounted cleanly or not) sooner that later
Fixes: ZX-3963 #done

Change-Id: I0741082f5a8740f9f851d483b8c8634bfd7d9c69