xfs/191: skip tests on older xfsprogs

xfs/191: skip tests on older xfsprogs

If we don't have temp file used to test on xfsprogs 3.2.2,
_require_xfs_mkfs_validation will fail because mkfs.xfs can't create
this file. We need to skip tests before xfsprogs 4.7.0, so fix it.

This feature was introduced in xfsprogs 4.2.0 by commit 20cec860e16b
("mkfs.xfs: always use underlying fs sector size when mkfs'ing a
file")

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>