net: phy: micrel: Add support for non PTP SKUs for lan8814

net: phy: micrel: Add support for non PTP SKUs for lan8814

The lan8814 has 4 different SKUs and for 2 of these SKUs the PTP is
disabled. All these SKUs have the same value in the register 2 and 3.
Meaning that we can't differentiate them based on device id, therefore
check the SKU register and based on this allow or not to create a PTP
device.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20251021070726.3690685-1-horatiu.vultur@microchip.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>