don't pass nameidata to ->follow_link()

its only use is getting passed to nd_jump_link(), which can obtain
it from current->nameidata

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index acd51d7..eb35874 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -393,7 +393,7 @@
 };
 #endif
 
-static const char *proc_follow_link(struct dentry *dentry, void **cookie, struct nameidata *nd)
+static const char *proc_follow_link(struct dentry *dentry, void **cookie)
 {
 	struct proc_dir_entry *pde = PDE(d_inode(dentry));
 	if (unlikely(!use_pde(pde)))