toybox: fix build with libxcrypt

pkgs/tools/misc/toybox/default.nix

···
 {
   stdenv, lib, fetchFromGitHub, which,
-  buildPackages,
+  buildPackages, libxcrypt,
   enableStatic ? stdenv.hostPlatform.isStatic,
   enableMinimal ? false,
   extraConfig ? ""
···
   };
 
   depsBuildBuild = [ buildPackages.stdenv.cc ]; # needed for cross
-  buildInputs = lib.optionals (enableStatic && stdenv.cc.libc ? static)
-    [ stdenv.cc.libc stdenv.cc.libc.static ];
+  buildInputs = [
+    libxcrypt
+  ] ++lib.optionals (enableStatic && stdenv.cc.libc ? static) [
+    stdenv.cc.libc
+    stdenv.cc.libc.static
+  ];
 
   postPatch = "patchShebangs .";