constify chmod_common/security_path_chmod

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/security/security.c b/security/security.c
index fc56765..b333429 100644
--- a/security/security.c
+++ b/security/security.c
@@ -485,7 +485,7 @@
 	return call_int_hook(path_truncate, 0, path);
 }
 
-int security_path_chmod(struct path *path, umode_t mode)
+int security_path_chmod(const struct path *path, umode_t mode)
 {
 	if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry))))
 		return 0;