Fixes gcc '-Wunused-but-set-variable' warning:

drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c: In function ibmvscsis_send_messages:
drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:1888:19: warning: variable iue set but not used [-Wunused-but-set-variable]
drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c: In function ibmvscsis_queue_data_in:
drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:3806:8: warning: variable sd set but not used [-Wunused-but-set-variable]

Link: https://lore.kernel.org/r/20191213064042.161840-1-chenzhou10@huawei.comReported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NChen Zhou <chenzhou10@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>