drm/i915/huc: Move HuC declarations into dedicated header

drm/i915/huc: Move HuC declarations into dedicated header

We want to keep each uC specific code in separate files.

Signed-off-by: Michal Wajdeczko <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Chris Wilson <[email protected]>
Cc: Sagar Arun Kamble <[email protected]>
Reviewed-by: Sagar Arun Kamble <[email protected]>
Reviewed-by: Joonas Lahtinen <[email protected]>
Signed-off-by: Joonas Lahtinen <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]