This reverts commit b95dc06a.

This workaround is no longer necessary.  We have a better workaround
in commit f95af4a9 ("drm/amdgpu: don't runtime suspend if there are displays attached (v3)").
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>