powerpc/85xx: introduce function serdes_device_from_fm_port()

In order to figure out which SerDes lane a given Fman port is connected
to, we need a function that maps the fm_port namespace to the srds_prtcl
namespace.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
2 files changed