driver: net: ldpaa: Update priv->phydev after free()

Even after memory free of phydev, priv is still pointing to the
obsolete address.
So update priv->phydev as NULL after memory free.

Signed-off-by: Prabhakar Kushwaha <prabhakar.kushwaha@nxp.com>
Signed-off-by: Ashish Kumar <Ashish.Kumar@nxp.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/ldpaa_eth/ldpaa_eth.c b/drivers/net/ldpaa_eth/ldpaa_eth.c
index 4e61700..f235b62 100644
--- a/drivers/net/ldpaa_eth/ldpaa_eth.c
+++ b/drivers/net/ldpaa_eth/ldpaa_eth.c
@@ -587,8 +587,10 @@
 #ifdef CONFIG_PHYLIB
 	if (priv->phydev && bus != NULL)
 		phy_shutdown(priv->phydev);
-	else
+	else {
 		free(priv->phydev);
+		priv->phydev = NULL;
+	}
 #endif
 
 	ldpaa_dpbp_free();