Setting of timestamps on devices had no effect visible to userland
because timestamps for devices were set in places that are never used.
This broke:
- update of file change time after a change of an attribute
- setting of file access and modification times.
The VA_UTIMES_NULL case did not work. Revs 1.31-1.32 were supposed to
fix this by copying correct bits from ufs, but had little or no effect
because the old checks were not removed.