[rom_ctrl] Add KAT for KMAC before ROM verification

For FIPS, we need to run a KAT on the KMAC app interface before staring the actual ROM verification. To keep things simple, I would suggest to bake a fixed test vector directly into the RTL and the FSM, rather than extracting the test vector and the resulting digest from the scrambled ROM.

This is also related to #30765 (we likely need to switch the algorithm).

Start at the KMAC app interface and the ROM-verification FSM in the RTL. Read issue #30765 first to confirm which algorithm and test vector remain valid, then trace how the FSM enters ROM verification. Done means a fixed KAT runs before verification and its result controls whether verification proceeds.

Written by the indexing model from the issue text.