oksh: link to ncurses

This fixes the ^L keybinding in emacs mode to properly clear the
screen.

pkgs/shells/oksh/default.nix

@@ -1,4 +1,9 @@
-{ stdenv, lib, fetchFromGitHub, buildPackages }:
+{ stdenv
+, lib
+, fetchFromGitHub
+, buildPackages
+, ncurses
+}:
 
 stdenv.mkDerivation rec {
   pname = "oksh";
@@ -19,6 +24,8 @@ stdenv.mkDerivation rec {
 
   configureFlags = [ "--no-strip" ];
 
+  buildInputs = [ ncurses ];
+
   meta = with lib; {
     description = "Portable OpenBSD ksh, based on the Public Domain Korn Shell (pdksh)";
     mainProgram = "oksh";