scsi: zfcp: update kernel message for invalid FCP_CMND length, it's not the CDB

[ Upstream commit 724e144387f4d7e7668d3da913d0efc44a9b4664 ]

The CDB is just a part inside of FCP_CMND, see zfcp_fc_scsi_to_fcp().
While at it, fix the device driver reaction: adapter not LUN shutdown.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>