drm/prime: Honor requested file flags when exporting a buffer

The DRM PRIME API passes file flags to the driver for the exported
buffer. Honor them instead of hardcoding 0600.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/drm_prime.c

@@ -190,8 +190,7 @@ struct dma_buf *drm_gem_prime_export(struct drm_device *dev,
 		if (ret)
 			return ERR_PTR(ret);
 	}
-	return dma_buf_export(obj, &drm_gem_prime_dmabuf_ops, obj->size,
-			      0600);
+	return dma_buf_export(obj, &drm_gem_prime_dmabuf_ops, obj->size, flags);
 }
 EXPORT_SYMBOL(drm_gem_prime_export);