switch touch_atime to struct path

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index a0b8276..0ccc74ee 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -642,7 +642,7 @@
 	cond_resched();
 	current->total_link_count++;
 
-	touch_atime(link->mnt, dentry);
+	touch_atime(link);
 	nd_set_link(nd, NULL);
 
 	error = security_inode_follow_link(link->dentry, nd);