drivers: net: fsl_enetc: use the new MDIO DM helper functions

Uses the new dm_eth_phy_connect helper to connect to the PHY to simplify
the code.

Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/fsl_enetc.h b/drivers/net/fsl_enetc.h
index 0bb4cdf..9a36cda 100644
--- a/drivers/net/fsl_enetc.h
+++ b/drivers/net/fsl_enetc.h
@@ -154,6 +154,7 @@
 
 	int if_type;
 	struct mii_dev imdio;
+	struct phy_device *phy;
 };
 
 /* register accessors */