LSM: Add security_path_chroot().

This patch allows pathname based LSM modules to check chroot() operations.

This hook is used by TOMOYO.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/security.c b/security/security.c
index 5259270..2797573 100644
--- a/security/security.c
+++ b/security/security.c
@@ -449,6 +449,11 @@
 		return 0;
 	return security_ops->path_chown(path, uid, gid);
 }
+
+int security_path_chroot(struct path *path)
+{
+	return security_ops->path_chroot(path);
+}
 #endif
 
 int security_inode_create(struct inode *dir, struct dentry *dentry, int mode)