drm/amd/display: Add YCBCR2020 coefficients to CSC matrix

When some of the IGT tests are executed in DCN31, it is possible to see
multiple occurrences of this warning:

 WARNING: CPU: 9 PID: 3482 at
 drivers/gpu/drm/amd/amdgpu/../dal-dev/dc/dcn30/dcn30_dpp.c:154
 dpp3_program_post_csc+0x196/0x220 [amdgpu]
 [..]
 PU: 9 PID: 3482 Comm: amd_hdr Tainted: G       W        5.18.0+ #3
 IP: 0010:dpp3_program_post_csc+0x196/0x220 [amdgpu]
 [..]
 all Trace:
 <TASK>
 dpp3_cnv_setup+0x5d9/0x5f0 [amdgpu]
 ? dcn20_blank_pixel_data+0x30a/0x330 [amdgpu]
 dcn20_program_pipe+0x259/0xb40 [amdgpu]
 ? offset_to_id+0x1b0/0x1c0 [amdgpu]
 dcn20_program_front_end_for_ctx+0x36a/0x450 [amdgpu]
 commit_planes_for_stream+0x8eb/0x13e0 [amdgpu]

This commit fix the above issue by adding YCBCR2020 coefficients to the
DPP Color Space Converter (CSC) matrix.

Reviewed-by: Nawwar Ali <nawwar.ali@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>