net: dsa: ocelot: remove interface checks

When the supported interfaces bitmap is populated, phylink will itself
check that the interface mode is present in this bitmap. Drivers no
longer need to perform this check themselves. Remove these checks.

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>