drivers: net: cpsw: Add support for new CPSW IP version

The new IP version has a minor changes and the offsets are same as the
previous version, so adding new IP version support in the driver.

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>