scsi: qedf: Remove set but not checked variable 'tmp'

scsi: qedf: Remove set but not checked variable 'tmp'

Looks like the return value of readw() has never been checked.

Fixes the following W=1 kernel build warning(s):

 drivers/scsi/qedf/qedf_main.c: In function ‘__qedf_probe’:
 drivers/scsi/qedf/qedf_main.c:3203:6: warning: variable ‘tmp’ set but not used [-Wunused-but-set-variable]

Link: https://lore.kernel.org/r/20200713074645.126138-10-lee.jones@linaro.org
Cc: QLogic-Storage-Upstream@cavium.com
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>