scsi: NCR5380: Return false instead of NULL

I overlooked this statement when I recently converted the function result
type from struct scsi_cmnd * to bool. No change to object code.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/NCR5380.c

@@ -1198,7 +1198,7 @@ static bool NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
 
 out:
 	if (!hostdata->selecting)
-		return NULL;
+		return false;
 	hostdata->selecting = NULL;
 	return ret;
 }