net: dsa: microchip: enable phy errata workaround on 9567

Also enable phy errata workaround on 9567 since has the same errata as
the 9477 according to the manufacture's documentation.

Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>