net: mscc: ocelot: offload redirect action to VCAP IS2

Via the OCELOT_MASK_MODE_REDIRECT flag put in the IS2 action vector, it
is possible to replace previous forwarding decisions with the port mask
installed in this rule.

I have studied Table 54 "MASK_MODE and PORT_MASK Combinations" from the
VSC7514 documentation and it appears to behave sanely when this rule is
installed in either lookup 0 or 1. Namely, a redirect in lookup 1 will
overwrite the forwarding decision taken by any entry in lookup 0.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>