drm/amdgpu: Remove unused pre_surface_trace
pre_surface_trace() has been unused since 2017's
commit 745cc746da42 ("drm/amd/display: remove
dc_pre_update_surfaces_to_stream from dc use")
Remove it.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
authored by