Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/start_kernel.h b/include/linux/start_kernel.h
index 4b268d8..8b369a4 100644
--- a/include/linux/start_kernel.h
+++ b/include/linux/start_kernel.h
@@ -9,5 +9,7 @@
    up something else. */
 
 extern asmlinkage void __init start_kernel(void);
+extern void __init arch_call_rest_init(void);
+extern void __ref rest_init(void);
 
 #endif /* _LINUX_START_KERNEL_H */