UNIPHY2 on the WAX630 is connected to a QCA8081 PHY which is only 2.5G and
it does not support using USXGMII at all but rather only SGMII or SGMII+.
Tested-by: Kristian Skramstad <kristian+github@83.no>
Signed-off-by: Robert Marko <robimarko@gmail.com>