libreswan: remove darwin from list of supported platforms

See discussion at #101543. Currently,
this build depends on iproute2 which is not available on darwin. This might be
fixed in the future by employing iproute2mac.

pkgs/tools/networking/libreswan/default.nix

@@ -86,7 +86,7 @@ stdenv.mkDerivation rec {
   meta = with stdenv.lib; {
     homepage = "https://libreswan.org";
     description = "A free software implementation of the VPN protocol based on IPSec and the Internet Key Exchange";
-    platforms = platforms.linux ++ platforms.darwin ++ platforms.freebsd;
+    platforms = platforms.linux ++ platforms.freebsd;
     license = licenses.gpl2;
     maintainers = [ maintainers.afranchuk ];
   };