This PR does four things, and shouldn't have visible impact to users. * Use fewer decimal places for D65 white point, to match e.g. sRGB and Rec.2020 standards. * Fix mistake in grayscale matrix for Grayscale look and False Color view transform. * Remove unused luminance_compensation_srgb/p3 * Improve AgX Log's matrix comment Pull Request: https://projects.blender.org/blender/blender/pulls/141027