Revert "drm/amdgpu: add param to specify fw bo location for front-door loading"

This reverts commit c572abff.

Will use debug module param instead of independent module param.

Signed-off-by: Le Ma <le.ma@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>