octeontx2-af: npc: cn20k: Fix MCAM actions read

octeontx2-af: npc: cn20k: Fix MCAM actions read

npc_cn20k_read_mcam_entry() always reloaded action and vtag_action from
bank 0 after programming the CAM words. Use the bank returned by
npc_get_bank() for the ACTION reads as well, and read those registers once
up front so both X2 and X4 paths share the same metadata.

Return directly from the X2 keyword path now that the action fields are
already populated.

Cc: Suman Ghosh <sumang@marvell.com>
Fixes: 6d1e70282f76 ("octeontx2-af: npc: cn20k: Use common APIs")
Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com>
Link: https://patch.msgid.link/20260429022722.1110289-8-rkannoth@marvell.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>