python3Packages.dlib: support sse4 instructions

My understanding of the line that is removed is, that the logic is
wrong. According to the setup.py file[0] it says that:

> To exclude certain options in the cmake config use --no:
>     for example:
>     --no USE_AVX_INSTRUCTIONS: will set -DUSE_AVX_INSTRUCTIONS=no

This means, that a true value of `avxSupport` will deactivate it in the
setup, which is not what we want.

[0]: https://github.com/davisking/dlib/blob/v19.21/setup.py#L22

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

@@ -1,4 +1,5 @@
 { buildPythonPackage, stdenv, lib, dlib, python, pytest, more-itertools
+, sse4Support ? stdenv.hostPlatform.sse4_1Support
 , avxSupport ? stdenv.hostPlatform.avxSupport
 }:
 
@@ -12,7 +13,10 @@ buildPythonPackage {
     ${python.interpreter} nix_run_setup test --no USE_AVX_INSTRUCTIONS
   '';
 
-  setupPyBuildFlags = lib.optional avxSupport "--no USE_AVX_INSTRUCTIONS";
+  setupPyBuildFlags = [
+    "--set USE_SSE4_INSTRUCTIONS=${if sse4Support then "yes" else "no"}"
+    "--set USE_AVX_INSTRUCTIONS=${if avxSupport then "yes" else "no"}"
+  ];
 
   patches = [ ./build-cores.patch ];