net: prestera: cache port state for non-phylink ports too

Port event data must stored to port-state cache regardless of whether
the port uses phylink or not since this data is used by ethtool.

Fixes: 52323ef7 ("net: marvell: prestera: add phylink support")
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Maksym Glubokiy <maksym.glubokiy@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>