net: dsa: mv88e6xxx: Add partial support for TCAM entries

net: dsa: mv88e6xxx: Add partial support for TCAM entries

This patch adds partial Ternary Content Addressable Memory (TCAM) for
the mv88e6390 and mv88e6393 family of switches. TCAM entries allow the
switch to match the first 48 or 96 bytes of a frame and take actions on
matched frames.

This patch introduces a subset of the available TCAM functionality.
Matching on ip addresses/protocol and trapping to the cpu.

Eg. to trap traffic with destination ip 224.0.1.129 to the cpu:

tc qdisc add dev p1 clsact
tc filter add dev p1 ingress protocol ip flower skip_sw \
    dst_ip 224.0.1.129 action trap

Signed-off-by: Cedric Jehasse <cedric.jehasse@luminex.be>
Link: https://patch.msgid.link/20260311-net-next-mv88e6xxx-tcam-v8-2-32dd5ba30002@luminex.be
Signed-off-by: Paolo Abeni <pabeni@redhat.com>