Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/drm/intel-gtt.h b/include/drm/intel-gtt.h
index 2324c84..71d8192 100644
--- a/include/drm/intel-gtt.h
+++ b/include/drm/intel-gtt.h
@@ -4,6 +4,9 @@
 #ifndef _DRM_INTEL_GTT_H
 #define	_DRM_INTEL_GTT_H
 
+#include <linux/agp_backend.h>
+#include <linux/kernel.h>
+
 void intel_gtt_get(u64 *gtt_total,
 		   phys_addr_t *mappable_base,
 		   resource_size_t *mappable_end);