EMC Symmetrix returns 'internal target error' for a variety of
conditions, most of which will be transient.  So we should always retry
it, even with failfast set.  Otherwise we'd get spurious path flaps with
multipath.
Signed-off-by: NMartin Wilck <mwilck@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>