modesetting: Add CTM RandR property

When the "CTM" (color transform matrix) modesetting property is available,
create a corresponding RandR property.

To match the format of the property available in the amdgpu driver, expose it as
an array of 18 32-bit XA_INTEGERs representing a 3x3 matrix in row-major order,
where each entry is a S31.32 sign-magnitude fixed-point number with the
fractional part listed first.

Signed-off-by: Aaron Plattner <>
Acked-by: Michel Dänzer <>
Reviewed-by: James Jones <>
4 jobs for modesetting-ctm in 6 minutes and 11 seconds (queued for 1 second)