roc-toolkit: add sox support

Sox is required for using roc-send with any input source other than PulseAudio.

pkgs/development/libraries/audio/roc-toolkit/default.nix

@@ -11,7 +11,9 @@
   libunwindSupport ? true,
   libunwind,
   pulseaudioSupport ? true,
-  libpulseaudio
+  libpulseaudio,
+  soxSupport ? true,
+  sox
 }:
 
 stdenv.mkDerivation rec {
@@ -36,15 +38,16 @@ stdenv.mkDerivation rec {
     libuv
   ] ++ lib.optional openfecSupport openfec
     ++ lib.optional libunwindSupport libunwind
-    ++ lib.optional pulseaudioSupport libpulseaudio;
+    ++ lib.optional pulseaudioSupport libpulseaudio
+    ++ lib.optional soxSupport sox;
 
   sconsFlags =
     [ "--build=${stdenv.buildPlatform.config}"
       "--host=${stdenv.hostPlatform.config}"
       "--prefix=${placeholder "out"}"
-      "--disable-sox"
       "--disable-doc"
       "--disable-tests" ] ++
+    lib.optional (!soxSupport) "--disable-sox" ++
     lib.optional (!libunwindSupport) "--disable-libunwind" ++
     lib.optional (!pulseaudioSupport) "--disable-pulseaudio" ++
     (if (!openfecSupport)