net: stmmac: dwc-qos-eth: use devm_kzalloc() for AXI data

Everywhere else in the driver uses devm_kzalloc() when allocating the
AXI data, so there is no kfree() of this structure. However,
dwc-qos-eth uses kzalloc(), which leads to this memory being leaked.
Switch to use devm_kzalloc().

Fixes: d8256121a9 ("stmmac: adding new glue driver dwmac-dwc-qos-eth")
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/E1tsRyv-0064nU-O9@rmk-PC.armlinux.org.uk
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/stmicro/stmmac/dwmac-dwc-qos-eth.c

@@ -46,7 +46,9 @@ static int dwc_eth_dwmac_config_dt(struct platform_device *pdev,
 	u32 a_index = 0;
 
 	if (!plat_dat->axi) {
-		plat_dat->axi = kzalloc(sizeof(struct stmmac_axi), GFP_KERNEL);
+		plat_dat->axi = devm_kzalloc(&pdev->dev,
+					     sizeof(struct stmmac_axi),
+					     GFP_KERNEL);
 
 		if (!plat_dat->axi)
 			return -ENOMEM;