i40e: Replace sscanf() with kstrtoint() in i40e_dbg_netdev_ops_write()

Commit 9fcdb1c ("i40e: remove read access to debugfs files")
introduced some checkpatch warnings like this:

  WARNING: Prefer kstrto<type> to single variable sscanf
  kernel-patches#240: FILE: drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1655:
  +               cnt = sscanf(&cmd_buf[11], "%i", &vsi_seid);

  WARNING: Prefer kstrto<type> to single variable sscanf
  kernel-patches#251: FILE: drivers/net/ethernet/intel/i40e/i40e_debugfs.c:1676:
  +               cnt = sscanf(&cmd_buf[4], "%i", &vsi_seid);

  total: 0 errors, 2 warnings, 0 checks, 194 lines checked

Function kstrtoint() provides better error detection, overflow protection,
and consistent error handling than sscanf(). Replace sscanf() with
kstrtoint() in i40e_dbg_netdev_ops_write() to silence the checkpatch
warnings.

Signed-off-by: Wang Liang <wangliang74@huawei.com>
Signed-off-by: NipaLocal <nipa@local>

Author: Wang Liang

drivers/net/ethernet/intel/i40e/i40e_debugfs.c

@@ -1604,7 +1604,7 @@ static ssize_t i40e_dbg_netdev_ops_write(struct file *filp,
 	int bytes_not_copied;
 	struct i40e_vsi *vsi;
 	int vsi_seid;
-	int i, cnt;
+	int i, ret;
 
 	/* don't allow partial writes */
 	if (*ppos != 0)
@@ -1629,9 +1629,9 @@ static ssize_t i40e_dbg_netdev_ops_write(struct file *filp,
 	if (strncmp(cmd_buf, "change_mtu", 10) == 0) {
 		int mtu;
 
-		cnt = sscanf(&cmd_buf[11], "%i %i",
+		ret = sscanf(&cmd_buf[11], "%i %i",
 			     &vsi_seid, &mtu);
-		if (cnt != 2) {
+		if (ret != 2) {
 			dev_info(&pf->pdev->dev, "change_mtu <vsi_seid> <mtu>\n");
 			goto netdev_ops_write_done;
 		}
@@ -1652,8 +1652,8 @@ static ssize_t i40e_dbg_netdev_ops_write(struct file *filp,
 		}
 
 	} else if (strncmp(cmd_buf, "set_rx_mode", 11) == 0) {
-		cnt = sscanf(&cmd_buf[11], "%i", &vsi_seid);
-		if (cnt != 1) {
+		ret = kstrtoint(&cmd_buf[11], 0, &vsi_seid);
+		if (ret) {
 			dev_info(&pf->pdev->dev, "set_rx_mode <vsi_seid>\n");
 			goto netdev_ops_write_done;
 		}
@@ -1673,8 +1673,8 @@ static ssize_t i40e_dbg_netdev_ops_write(struct file *filp,
 		}
 
 	} else if (strncmp(cmd_buf, "napi", 4) == 0) {
-		cnt = sscanf(&cmd_buf[4], "%i", &vsi_seid);
-		if (cnt != 1) {
+		ret = kstrtoint(&cmd_buf[4], 0, &vsi_seid);
+		if (ret) {
 			dev_info(&pf->pdev->dev, "napi <vsi_seid>\n");
 			goto netdev_ops_write_done;
 		}