stop passing nameidata * to ->d_revalidate()

Just the lookup flags.  Die, bastard, die...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index ed9fbc2..56750b7 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -431,3 +431,8 @@
 	d_alloc_root() is gone, along with a lot of bugs caused by code
 misusing it.  Replacement: d_make_root(inode).  The difference is,
 d_make_root() drops the reference to inode if dentry allocation fails.  
+
+--
+[mandatory]
+	The witch is dead!  Well, 1/3 of it, anyway.  ->d_revalidate() does *not*
+take struct nameidata anymore; just the flags.