net: lan743x: Add support for OTP

Add new the OTP read and write access functions for PCI11010/PCI11414 chips
PCI11010/PCI11414 OTP module register offsets are different from
LAN743x OTP module

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>