init: mark create_dev as __init

This helper is only used for the early init code.
Signed-off-by: Christoph Hellwig <hch@lst.de>

init/do_mounts.h

@@ -13,7 +13,7 @@ void  mount_block_root(char *name, int flags);
 void  mount_root(void);
 extern int root_mountflags;
 
-static inline int create_dev(char *name, dev_t dev)
+static inline __init int create_dev(char *name, dev_t dev)
 {
 	ksys_unlink(name);
 	return ksys_mknod(name, S_IFBLK|0600, new_encode_dev(dev));