drm/amd/display: Set Cursor Matrix to bypass instead of Input Plane

why:
When the cursor disappears/reappears on fullscreen video, there is a
short transitional period where the cursor's color matrix is using the
same format as the video plane. This sets the cursor to the wrong color
momentarily before the UI plane appears, correcting the color.

how:
Instead of defaulting to using the color space from the input plane,
default to bypass mode.

Reviewed-by: Nevenko Stupar <nevenko.stupar@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Daniel Sa <daniel.sa@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>