net: mvpp2: cls: use Lookup Type in classification engines

The PPv2 classifier allows to perform multiple lookups on the same
engine when classifying a packet. These lookups can match similar parts
of a packet header, but perform different actions upon matching. To
differentiate these types of lookups, it's possible to specify a Lookup
Type in the flow table entries, which will be part of the key for the
lookup engines.

This commit introduces the use of Lookup Types for C2 matches. Since for
now we only perform C2 lookups to enable RSS, we only need one Lookup
Type.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>