Certain PHY settings need to be configurable by UEFI depending on the
platform being used.  Add new device tree / ACPI properties that, if
present, will override the pre-determined values currently used.
Signed-off-by: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>