octeontx2-af: add support for multicast/promisc packet replication feature

Currently, multicast packet filtering is accomplished by installing
MCAM rule that matches all-multicast MAC address and has its
NPC_RX_ACTION set to unicast to PF. Similarly promisc feature is
achieved by installing MCAM rule that matches all the traffic received
by the channel and unicast the packets to PF. This approach only applies
to PF and is not scalable across VFs.

This patch adds support for PF/VF multicast and promisc feature by
reserving NIX_RX_MCE_S entries from the global MCE list allocated
during NIX block initialization. The NIX_RX_MCE_S entries create a
linked list with a flag indicating the end of the list, and each entry
points to a PF_FUNC (either PF or VF). When a packet NPC_RX_ACTION is
set to MCAST, the corresponding NIX_RX_MCE_S list is traversed and the
packet is queued to each PF_FUNC available on the list.

The PF or VF driver adds the multicast/promisc packet match entry and
updates the MCE list with correspondng PF_FUNC. When a PF or VF interface
is disabled, the corresponding NIX_RX_MCE_S entry is removed from the
MCE list and the MCAM entry will be disabled if the list is empty.

Signed-off-by: Naveen Mamindlapalli <naveenm@marvell.com>
Signed-off-by: Sunil Kovvuri Goutham <Sunil.Goutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>