add wrapper for g++ (in addition to gcc)

esp32-tools.nix

@@ -7,6 +7,8 @@ let
     mkdir -p $out/bin
     ln -s ${pkg}/bin/gcc $out/bin/${pkg.stdenv.targetPlatform.config}-gcc
     ln -s ${pkg}/bin/gcc $out/bin/${pkg.stdenv.targetPlatform.config}-wrapped-gcc
+    ln -s ${pkg}/bin/g++ $out/bin/${pkg.stdenv.targetPlatform.config}-g++
+    ln -s ${pkg}/bin/g++ $out/bin/${pkg.stdenv.targetPlatform.config}-wrapped-g++
   '';
 
   # If Nix is cross-compiling this package, we have build!=host!=target (but Nix doesn't know about target, which is ESP32).