scsi: lpfc: Fix crash in lpfc nvmet when fc port is reset

In adapter reset tests, an oops was seen with a NULL pointer in
lpfc_free_rq_buffer+0x20/0x60

The driver is failing to properly repost the nvmet sgl list when
recovering from the reset. Thus the driver eventually trys to walk an
errant buffer list.

Corrected the sgl buffer recovery as well as strengthening the
initialization of the bufferlist.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>