If the nvmet_fc transport breaks an io into multiple sequences, the
driver will improperly set the relative offset on the 2nd through N
sequences.

Correct by properly formatting the hw cmd so the relative offset is
picked up from the hw cmd.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>