Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index 8d8821b..659a440 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -134,7 +134,7 @@
 	WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
 }
 
-static __always_inline bool
+static __always_inline __must_check bool
 check_copy_size(const void *addr, size_t bytes, bool is_source)
 {
 	int sz = __compiletime_object_size(addr);