python3Packages.pyzmq: fix build

Tested building a few packages that depend on it too: circus,
jupyter-client, logbook, partd, rpcq, tornado, zerorpc.

Fixes: e597af5583 ("zeromq: enable curve support")

pkgs/development/python-modules/pyzmq/default.nix

@@ -18,6 +18,7 @@
   python,
   pythonOlder,
   tornado,
+  libsodium,
   zeromq,
   pytest-asyncio,
 }:
@@ -44,7 +45,10 @@ buildPythonPackage rec {
 
   dontUseCmakeConfigure = true;
 
-  buildInputs = [ zeromq ];
+  buildInputs = [
+    libsodium
+    zeromq
+  ];
 
   dependencies = lib.optionals isPyPy [ cffi ];