phylib: Basic support for the M88E1121R Marvell chip

Add support for the Marvell M88E1121R Dual GigE PHY

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Sergei Poselenov <sposelenov@emcraft.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>