scsi: qla4xxx: remove unnecessary condition check for dma_pool_destroy()

dma_pool_destroy() can handle NULL pointer correctly, so there is no
need to check NULL pointer before calling dma_pool_destroy().
Signed-off-by: NChengguang Xu <cgxu519@gmx.com>
Acked-by: NManish Rangankar <Manish.Rangankar@cavium.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla4xxx/ql4_os.c

@@ -4165,15 +4165,13 @@ static void qla4xxx_mem_free(struct scsi_qla_host *ha)
 
 	ha->srb_mempool = NULL;
 
-	if (ha->chap_dma_pool)
-		dma_pool_destroy(ha->chap_dma_pool);
+	dma_pool_destroy(ha->chap_dma_pool);
 
 	if (ha->chap_list)
 		vfree(ha->chap_list);
 	ha->chap_list = NULL;
 
-	if (ha->fw_ddb_dma_pool)
-		dma_pool_destroy(ha->fw_ddb_dma_pool);
+	dma_pool_destroy(ha->fw_ddb_dma_pool);
 
 	/* release io space registers  */
 	if (is_qla8022(ha)) {