meson: Don't set CC and CXX

I've since convinced upstream to not use such vars for the build
platform during cross. Finally!

pkgs/development/tools/build-managers/meson/default.nix

@@ -90,8 +90,6 @@ python3Packages.buildPythonApplication rec {
   # checkInputs = [ ninja pkgconfig ];
   # checkPhase = "python ./run_project_tests.py";
 
-  inherit (stdenv) cc;
-
   isCross = stdenv.targetPlatform != stdenv.hostPlatform;
 
   meta = with lib; {

pkgs/development/tools/build-managers/meson/setup-hook.sh

@@ -25,7 +25,7 @@ mesonConfigurePhase() {
 
     echo "meson flags: $mesonFlags ${mesonFlagsArray[@]}"
 
-    CC=@cc@/bin/cc CXX=@cc@/bin/c++ meson build $mesonFlags "${mesonFlagsArray[@]}"
+    meson build $mesonFlags "${mesonFlagsArray[@]}"
     cd build
 
     if ! [[ -v enableParallelBuilding ]]; then