scsi: aha152x: Remove unused variable 'ret'

Looks to be unused since 2014.

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

 drivers/scsi/aha152x.c: In function ‘datai_run’:
 drivers/scsi/aha152x.c:2033:9: warning: variable ‘data’ set but not used [-Wunused-but-set-variable]
 2033 | int data;
 | ^~~~

Link: https://lore.kernel.org/r/20200707140055.2956235-7-lee.jones@linaro.org
Cc: "Juergen E. Fischer" <fischer@norbit.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/aha152x.c

@@ -2030,8 +2030,7 @@ static void datai_run(struct Scsi_Host *shpnt)
 				    fifodata, GETPORT(FIFOSTAT));
 			SETPORT(DMACNTRL0, ENDMA|_8BIT);
 			while(fifodata>0) {
-				int data;
-				data=GETPORT(DATAPORT);
+				GETPORT(DATAPORT);
 				fifodata--;
 				DATA_LEN++;
 			}