libweston: add weston_output::color_profile

Add API to set an output's color profile. This new function can also be
called while the output is enabled. This allows changing the output
color profile even at runtime if desired.

color-noop has no way of creating weston_color_profile objects, so it
just asserts that no color profile is set.

color-lcms does not yet implement taking the output color profile into
account, so for now it just fails everything if a profile is set.

weston_surface_color_transform_fini() was previously used only prior to
freeing the struct, but now it is used also to just clear the struct,
hence it needs to reset the fields.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

include/libweston/libweston.h

@@ -374,6 +374,7 @@ struct weston_output {
 	bool enabled; /**< is in the output_list, not pending list */
 	int scale;
 
+	struct weston_color_profile *color_profile;
 	struct weston_color_transform *from_sRGB_to_output;
 	struct weston_color_transform *from_sRGB_to_blend;
 	struct weston_color_transform *from_blend_to_output;
@@ -2083,6 +2084,10 @@ void
 weston_output_set_transform(struct weston_output *output,
 			    uint32_t transform);
 
+bool
+weston_output_set_color_profile(struct weston_output *output,
+				struct weston_color_profile *cprof);
+
 void
 weston_output_init(struct weston_output *output,
 		   struct weston_compositor *compositor,