octeontx2: cn20k: Respect NPC MCAM X2/X4 profile in flows and DFT alloc

octeontx2: cn20k: Respect NPC MCAM X2/X4 profile in flows and DFT alloc

Default CN20K NPC rule allocation now keys off the active MCAM keyword
width: use X4 with a bank-masked reference index when the silicon uses
X4 keys, and X2 with the raw index otherwise (replacing the previous
always-X2 / eidx + 1 behaviour).

In the AF flow-install path, flows that need more than 256 key bits
query the NPC profile; if the platform is fixed to X2 entries, fail
with -EOPNOTSUPP instead of requesting X4. Otherwise select X4 for the
MCAM alloc.

On the PF, cache and pass the profile kw_type from npc_get_pfl_info
through otx2_mcam_pfl_info_get(), and use it when allocating MCAM
entries for RSS/defaults and when installing ethtool flows on CN20K,
including masking the reference index for X4 slot layout.

Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com>
Link: https://patch.msgid.link/20260609040453.711932-9-rkannoth@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>