Restrict some code to StoreDirConfig

- part of eval cache
 - part of derivations
 - derived path
 - store path with outputs
 - serializers

src/libstore/builtins/buildenv.cc

@@ -1,4 +1,5 @@
 #include "buildenv.hh"
+#include "derivations.hh"
 
 #include <sys/stat.h>
 #include <sys/types.h>

src/libstore/builtins/buildenv.hh

@@ -1,7 +1,6 @@
 #pragma once
 ///@file
 
-#include "derivations.hh"
 #include "store-api.hh"
 
 namespace nix {