NFSv4: Replace lock_owner->ld_id with an ida based allocator

Again, We're unlikely to ever need more than 2^31 simultaneous lock
owners, so let's replace the custom allocator.

Now that there are no more users, we can also get rid of the custom
allocator code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 1dd2e40..9c77af9 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -4017,7 +4017,7 @@
 	if (status != 0)
 		goto out;
 	lsp = request->fl_u.nfs4_fl.owner;
-	arg.lock_owner.id = lsp->ls_id.id;
+	arg.lock_owner.id = lsp->ls_id;
 	arg.lock_owner.s_dev = server->s_dev;
 	status = nfs4_call_sync(server->client, server, &msg, &arg.seq_args, &res.seq_res, 1);
 	switch (status) {
@@ -4262,7 +4262,7 @@
 		goto out_free_seqid;
 	p->arg.lock_stateid = &lsp->ls_stateid;
 	p->arg.lock_owner.clientid = server->nfs_client->cl_clientid;
-	p->arg.lock_owner.id = lsp->ls_id.id;
+	p->arg.lock_owner.id = lsp->ls_id;
 	p->arg.lock_owner.s_dev = server->s_dev;
 	p->res.lock_seqid = p->arg.lock_seqid;
 	p->lsp = lsp;
@@ -4679,7 +4679,7 @@
 	if (!args)
 		return;
 	args->lock_owner.clientid = server->nfs_client->cl_clientid;
-	args->lock_owner.id = lsp->ls_id.id;
+	args->lock_owner.id = lsp->ls_id;
 	args->lock_owner.s_dev = server->s_dev;
 	msg.rpc_argp = args;
 	rpc_call_async(server->client, &msg, 0, &nfs4_release_lockowner_ops, args);