This adds basic support for asics that use atomfirmware.h
to define their vbios tables.

v2: rebase
v3: squash in num scratch reg fix
Acked-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NKen Wang <Qingqing.Wang@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>