scsi: 3w-9xxx: Remove a few set but unused variables

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

 drivers/scsi/3w-9xxx.c: In function ‘twa_empty_response_queue’:
 drivers/scsi/3w-9xxx.c:942:24: warning: variable ‘response_que_value’ set but not used [-Wunused-but-set-variable]
 drivers/scsi/3w-9xxx.c: In function ‘twa_scsi_biosparam’:
 drivers/scsi/3w-9xxx.c:1701:23: warning: variable ‘tw_dev’ set but not used [-Wunused-but-set-variable]
 drivers/scsi/3w-9xxx.c: In function ‘twa_scsiop_execute_scsi’:
 drivers/scsi/3w-9xxx.c:1812:22: warning: variable ‘sglist’ set but not used [-Wunused-but-set-variable]

Link: https://lore.kernel.org/r/20210312094738.2207817-30-lee.jones@linaro.org
Cc: Adam Radford <aradford@gmail.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/3w-9xxx.c

@@ -939,13 +939,13 @@ static int twa_decode_bits(TW_Device_Extension *tw_dev, u32 status_reg_value)
 /* This function will empty the response queue */
 static int twa_empty_response_queue(TW_Device_Extension *tw_dev)
 {
-	u32 status_reg_value, response_que_value;
+	u32 status_reg_value;
 	int count = 0, retval = 1;
 
 	status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));
 
 	while (((status_reg_value & TW_STATUS_RESPONSE_QUEUE_EMPTY) == 0) && (count < TW_MAX_RESPONSE_DRAIN)) {
-		response_que_value = readl(TW_RESPONSE_QUEUE_REG_ADDR(tw_dev));
+		readl(TW_RESPONSE_QUEUE_REG_ADDR(tw_dev));
 		status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));
 		count++;
 	}
@@ -1698,9 +1698,6 @@ static int twa_reset_sequence(TW_Device_Extension *tw_dev, int soft_reset)
 static int twa_scsi_biosparam(struct scsi_device *sdev, struct block_device *bdev, sector_t capacity, int geom[])
 {
 	int heads, sectors, cylinders;
-	TW_Device_Extension *tw_dev;
-
-	tw_dev = (TW_Device_Extension *)sdev->host->hostdata;
 
 	if (capacity >= 0x200000) {
 		heads = 255;
@@ -1809,14 +1806,11 @@ static int twa_scsiop_execute_scsi(TW_Device_Extension *tw_dev, int request_id,
 	u32 num_sectors = 0x0;
 	int i, sg_count;
 	struct scsi_cmnd *srb = NULL;
-	struct scatterlist *sglist = NULL, *sg;
+	struct scatterlist *sg;
 	int retval = 1;
 
-	if (tw_dev->srb[request_id]) {
+	if (tw_dev->srb[request_id])
 		srb = tw_dev->srb[request_id];
-		if (scsi_sglist(srb))
-			sglist = scsi_sglist(srb);
-	}
 
 	/* Initialize command packet */
 	full_command_packet = tw_dev->command_packet_virt[request_id];