[PATCH V2] drm/plane-helper: Add the missing declaration of drm_atomic_state

[Ma Jun]

Add the missing declaration of struct drm_atomic_state to fix the
compile error below:

error: 'struct drm_atomic_state' declared inside parameter
list will not be visible outside of this definition or declaration [-Werror]

Signed-off-by: Ma Jun <majun at amd.com>
---
 include/drm/drm_plane_helper.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/drm/drm_plane_helper.h b/include/drm/drm_plane_helper.h
index b00ad36cf5b6..90156e13ac11 100644
--- a/include/drm/drm_plane_helper.h
+++ b/include/drm/drm_plane_helper.h
@@ -26,6 +26,7 @@
 
 #include <linux/types.h>
 
+struct drm_atomic_state;
 struct drm_crtc;
 struct drm_framebuffer;
 struct drm_modeset_acquire_ctx;
-- 
2.25.1