net: phy: Add clause 45 identifier to phy_device

The phy devices can be accessed via clause 22 or via clause 45.
This information can be deduced when we read phy id. if the phy id
is read without giving any MDIO Manageable Device Address (MMD), then
it conforms to clause 22. otherwise it conforms to clause 45.

Signed-off-by: Pankaj Bansal <pankaj.bansal@nxp.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>

include/phy.h

@@ -138,6 +138,7 @@ struct phy_device {
 	int pause;
 	int asym_pause;
 	u32 phy_id;
+	bool is_c45;
 	u32 flags;
 };