drm/amdgpu: Fix kernel-doc comments for some LUT properties

drm/amdgpu: Fix kernel-doc comments for some LUT properties

The following members of struct amdgpu_mode_info do not have valid
references in the related kernel-doc sections:

 - plane_shaper_lut_property
 - plane_shaper_lut_size_property,
 - plane_lut3d_size_property

Correct all affected comment blocks.

Fixes: f545d82479b4 ("drm/amd/display: add plane shaper LUT and TF driver-specific properties")
Fixes: 671994e3bf33 ("drm/amd/display: add plane 3D LUT driver-specific properties")
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>