scsi: cxlflash: Remove unnecessary existence check
The AFU termination sequence has been refactored over time such that the
main tear down routine, term_afu(), can no longer can be invoked with a
NULL AFU pointer. Remove the unnecessary existence check from
term_afu().
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>