proc: spread __init

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

fs/proc/proc_devtree.c

@@ -4,6 +4,7 @@
  * Copyright 1997 Paul Mackerras
  */
 #include <linux/errno.h>
+#include <linux/init.h>
 #include <linux/time.h>
 #include <linux/proc_fs.h>
 #include <linux/stat.h>
@@ -214,7 +215,7 @@ void proc_device_tree_add_node(struct device_node *np,
 /*
  * Called on initialization to set up the /proc/device-tree subtree
  */
-void proc_device_tree_init(void)
+void __init proc_device_tree_init(void)
 {
 	struct device_node *root;
 	if ( !have_of )