net: phy: move marking PHY on SFP module into SFP code

Move marking the PHY as being on a SFP module into the SFP code between
getting the PHY device (and thus initialising the phy_device structure)
and registering the discovered device.

This means that PHY drivers can use phy_on_sfp() in their match and
get_features methods.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/E1qRaga-001vKt-8X@rmk-PC.armlinux.org.ukSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/phy/phy_device.c

@@ -1489,8 +1489,6 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev,
 
 		if (phydev->sfp_bus_attached)
 			dev->sfp_bus = phydev->sfp_bus;
-		else if (dev->sfp_bus)
-			phydev->is_on_sfp_module = true;
 	}
 
 	/* Some Ethernet drivers try to connect to a PHY device before

drivers/net/phy/sfp.c

@@ -1763,6 +1763,9 @@ static int sfp_sm_probe_phy(struct sfp *sfp, int addr, bool is_c45)
 		return PTR_ERR(phy);
 	}
 
+	/* Mark this PHY as being on a SFP module */
+	phy->is_on_sfp_module = true;
+
 	err = phy_device_register(phy);
 	if (err) {
 		phy_device_free(phy);