[Why]
We're missing the helpers from dcn20 that would allow
overriding these with DC debug options.
[How]
Use dcn20_patch_bounding_box to support overriding all the
relevant values.
Reviewed-by: Jun Lei <Jun.Lei@amd.com> Acked-by: Alan Liu <HaoPing.Liu@amd.com> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>