net: hns3: fix incorrect resp_msg issue

In hclge_mbx_handler(), if there are two consecutive mailbox
messages that requires resp_msg, the resp_msg is not cleared
after processing the first message, which will cause the resp_msg
data of second message incorrect.

Fix it by clearing the resp_msg before processing every mailbox
message.

Fixes: bb5790b7 ("net: hns3: refactor mailbox response scheme between PF and VF")
Signed-off-by: Jiaran Zhang <zhangjiaran@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_mbx.c

@@ -710,7 +710,6 @@ void hclge_mbx_handler(struct hclge_dev *hdev)
 	unsigned int flag;
 	int ret = 0;
 
-	memset(&resp_msg, 0, sizeof(resp_msg));
 	/* handle all the mailbox requests in the queue */
 	while (!hclge_cmd_crq_empty(&hdev->hw)) {
 		if (test_bit(HCLGE_STATE_CMD_DISABLE, &hdev->state)) {
@@ -738,6 +737,9 @@ void hclge_mbx_handler(struct hclge_dev *hdev)
 
 		trace_hclge_pf_mbx_get(hdev, req);
 
+		/* clear the resp_msg before processing every mailbox message */
+		memset(&resp_msg, 0, sizeof(resp_msg));
+
 		switch (req->msg.code) {
 		case HCLGE_MBX_MAP_RING_TO_VECTOR:
 			ret = hclge_map_unmap_ring_to_vf_vector(vport, true,