The intel driver uses the same logic to attach the Colorspace property
in multiple places and we'll need it in vc4 too. Let's move that common
code in a helper.
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210430094451.2145002-4-maxime@cerno.tech