output: drop output timeline flag

This has been superseded by the backend-wide feature flag.

backend/drm/drm.c

@@ -1650,11 +1650,6 @@ static bool connect_drm_connector(struct wlr_drm_connector *wlr_conn,
 		output->non_desktop = non_desktop;
 	}
 
-	output->timeline = drm->iface != &legacy_iface;
-	if (drm->parent) {
-		output->timeline = output->timeline && drm->mgpu_renderer.wlr_rend->features.timeline;
-	}
-
 	memset(wlr_conn->max_bpc_bounds, 0, sizeof(wlr_conn->max_bpc_bounds));
 	if (wlr_conn->props.max_bpc != 0) {
 		if (!introspect_drm_prop_range(drm->fd, wlr_conn->props.max_bpc,

include/wlr/types/wlr_output.h

@@ -171,8 +171,6 @@ struct wlr_output {
 
 	// true for example with VR headsets
 	bool non_desktop;
-	// Whether wait/signal timelines are supported
-	bool timeline;
 
 	// Commit sequence number. Incremented on each commit, may overflow.
 	uint32_t commit_seq;