xfs/279: skip test if we can't allocate scsi_debug device

Due to the unique structure of xfs/279 running _get_scsi_debug_dev from
a backtick from inside subshell, the "could not get scsi_debug device"
checks do not actually stop the test when modprobe scsi_debug fails.

Therefore, check the value of SCSI_DEBUG_DEV from the subshell and
_notrun the test if we couldn't get memory.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
1 file changed