drm/gem-fb-helper: Use debug message on gem lookup failure

GEM lookup failure can easily be triggered by userspace so make
it a debug message, not an error message.

Also remove unnecessary inner parentheses and fix alphabetical
struct declaration order.

Cc: Laurent Pinchart <[e-mail]>
Signed-off-by: Noralf Trønnes <[e-mail]>
Reviewed-by: Daniel Vetter <[e-mail]>
Reviewed-by: Laurent Pinchart <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/drm_gem_framebuffer_helper.c

···
 
 		objs[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]);
 		if (!objs[i]) {
-			DRM_DEV_ERROR(dev->dev, "Failed to lookup GEM\n");
+			DRM_DEBUG_KMS("Failed to lookup GEM object\n");
 			ret = -ENOENT;
 			goto err_gem_object_put;
 		}
···
 	struct dma_buf *dma_buf;
 	struct dma_fence *fence;
 
-	if ((plane->state->fb == state->fb) || !state->fb)
+	if (plane->state->fb == state->fb || !state->fb)
 		return 0;
 
 	dma_buf = drm_gem_fb_get_obj(state->fb, 0)->dma_buf;

include/drm/drm_gem_framebuffer_helper.h

···
 #define __DRM_GEM_FB_HELPER_H__
 
 struct drm_device;
-struct drm_file;
 struct drm_fb_helper_surface_size;
+struct drm_file;
 struct drm_framebuffer;
 struct drm_framebuffer_funcs;
 struct drm_gem_object;