drm/amd/display: Promote DAL to 3.2.238

Acked-by: Stylon Wang <stylon.wang@amd.com>
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>