generic/402: skip test if xfs_io can't parse the date value

generic/402: skip test if xfs_io can't parse the date value

If xfs_io's utimes command cannot interpret the arguments that are
given to it, it will print out "Bad value for [am]time".  Detect
when this happens and drop the file out of the test entirely.

This is particularly noticeable on 32-bit platforms and the largest
timestamp seconds supported by the filesystem is INT_MAX.  In this
case, the maximum value we can cram into tv_sec is INT_MAX, and
there is no way to actually test setting a timestamp of INT_MAX + 1
to test the clamping.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>