xwax: fix the build (missing alsa-lib input) (#402378)

pkgs/by-name/xw/xwax/package.nix

@@ -4,6 +4,7 @@
   fetchurl,
   SDL,
   SDL_ttf,
+  alsa-lib,
   jack2,
   libmpg123,
   ffmpeg,
@@ -38,6 +39,8 @@ stdenv.mkDerivation (finalAttrs: {
     SDL
     SDL_ttf
 
+    alsa-lib
+
     # audio server
     jack2
 
@@ -55,6 +58,8 @@ stdenv.mkDerivation (finalAttrs: {
     "--enable-jack"
   ];
 
+  enableParallelBuilding = true;
+
   nativeInstallCheckInputs = [ versionCheckHook ];
   versionCheckProgramArg = "-h";
   doInstallCheck = true;