alsa-utils: wrap all binaries with ALSA_PLUGIN_DIR

pkgs/by-name/al/alsa-utils/package.nix

···
         procps
       ]
     }"
-    wrapProgram $out/bin/aplay --set-default ALSA_PLUGIN_DIR ${plugin-dir}
+    for program in $out/bin/*; do
+        wrapProgram "$program" --set-default ALSA_PLUGIN_DIR "${plugin-dir}"
+    done
   '';
 
   postInstall = ''