drm/i915: Announce support for framebuffer modifiers

Let the DRM core know we can handle it.

v2: Change to boolean true. (Daniel Vetter)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -13169,6 +13169,8 @@ void intel_modeset_init(struct drm_device *dev)
 	dev->mode_config.preferred_depth = 24;
 	dev->mode_config.prefer_shadow = 1;
 
+	dev->mode_config.allow_fb_modifiers = true;
+
 	dev->mode_config.funcs = &intel_mode_funcs;
 
 	intel_init_quirks(dev);