net: phy: xgmiitorgmii: Fix non static symbol warning

Fixes the following sparse warning:

drivers/net/phy/xilinx_gmii2rgmii.c:61:5: warning:
symbol 'xgmiitorgmii_probe' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/phy/xilinx_gmii2rgmii.c

···
 	return 0;
 }
 
-int xgmiitorgmii_probe(struct mdio_device *mdiodev)
+static int xgmiitorgmii_probe(struct mdio_device *mdiodev)
 {
 	struct device *dev = &mdiodev->dev;
 	struct device_node *np = dev->of_node, *phy_node;