octeontx2-af: Add support for Tx packet marking

NIX_AF_MARK_FORMAT(0..127)_CTL register enables an SW defined
means to mark/insert various data in the packet based on
final packet color from traffic shaping HW.

0..127 works as an index to choose the algorithm. On success,
the mailbox returns the index to the client.

Add NIX_MARK_FORMAT_CFG mailbox which reserves mark format based on
tuple (offset, y_mask, y_val, r_mask, r_val)

If the tuple is requested again for mark format that was already
reserved, then it will be reused. If not it will reserve a new entry
if space is available.

Also on AF init commonly used marker format such as VLAN DEI, IPv4
ECN, IPv4 DSCP are reserved for AF consumers.

Signed-off-by: Krzysztof Kanas <kkanas@marvell.com>
Signed-off-by: Jerin Jacob <jerinj@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>