graphics: allow re-saturation for any legacy dataspace

While our intention is to only re-saturate legacy sRGB, the
re-saturation is usually performed globally by the composer.  To
avoid GPU fallback when, for example, video plays, allow the
re-saturation to be applied on any legacy dataspace.

This also removes the clamping after applying the re-saturation
matrix, allowing the output dataspace to be scRGB.

Bug: 78303195
Bug: 78025845
Test: manual
Change-Id: Ic221401894789fbaf6bad944b49006163238237c