scsi: qla1280: Remove set but not used variable in qla1280_nvram_config()

This addresses the following gcc warning with "make W=1":

drivers/scsi/qla1280.c: In function ‘qla1280_nvram_config’:
drivers/scsi/qla1280.c:2188:36: warning: variable ‘ddma_conf’ set but
not used [-Wunused-but-set-variable]
 2188 |   uint16_t hwrev, cfg1, cdma_conf, ddma_conf;
      |                                    ^~~~~~~~~

Link: https://lore.kernel.org/r/20200907074518.2326360-3-yanaijie@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla1280.c

@@ -2184,13 +2184,12 @@ qla1280_nvram_config(struct scsi_qla_host *ha)
 		nv->cntr_flags_1.disable_loading_risc_code;
 
 	if (IS_ISP1040(ha)) {
-		uint16_t hwrev, cfg1, cdma_conf, ddma_conf;
+		uint16_t hwrev, cfg1, cdma_conf;
 
 		hwrev = RD_REG_WORD(&reg->cfg_0) & ISP_CFG0_HWMSK;
 
 		cfg1 = RD_REG_WORD(&reg->cfg_1) & ~(BIT_4 | BIT_5 | BIT_6);
 		cdma_conf = RD_REG_WORD(&reg->cdma_cfg);
-		ddma_conf = RD_REG_WORD(&reg->ddma_cfg);
 
 		/* Busted fifo, says mjacob. */
 		if (hwrev != ISP_CFG0_1040A)