drm/radeon/cik: Add support for new ucode format (v5)

This adds CIK support for the new ucode format.

v2: add size validation, integrate debug info
v3: add support for MEC2 on KV
v4: fix typos
v4: update to latest format

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>