net: mdio: Use of_property_count_u32_elems() to get property length

Replace of_get_property() with the type specific
of_property_count_u32_elems() to get the property length.

This is part of a larger effort to remove callers of of_get_property()
and similar functions. of_get_property() leaks the DT property data
pointer which is a problem for dynamically allocated nodes which may
be freed.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20240731201514.1839974-2-robh@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/mdio/of_mdio.c

@@ -390,7 +390,7 @@ EXPORT_SYMBOL(of_phy_get_and_connect);
 bool of_phy_is_fixed_link(struct device_node *np)
 {
 	struct device_node *dn;
-	int len, err;
+	int err;
 	const char *managed;
 
 	/* New binding */
@@ -405,8 +405,7 @@ bool of_phy_is_fixed_link(struct device_node *np)
 		return true;
 
 	/* Old binding */
-	if (of_get_property(np, "fixed-link", &len) &&
-	    len == (5 * sizeof(__be32)))
+	if (of_property_count_u32_elems(np, "fixed-link") == 5)
 		return true;
 
 	return false;