revert overlay to get stdlib update in first

Author: timfel

ci.jsonnet

@@ -1,5 +1,5 @@
 {
-  overlay: "c25b1177db93290c2643d44f5eebc9f6ee4adac9",
+  overlay: "d20cc2abdeb3cfb022e1a8035e40e350e5cfe5fc",
 
   // ======================================================================================================
   //
@@ -74,8 +74,6 @@
       "python": "==3.4.1",
       "libffi": ">=3.2.1",
       "bzip2": ">=1.0.6",
-      "make": ">=3.83",
-      "binutils": "==2.23.2",
     },
     downloads +: {
       LIBGMP: utils.download("libgmp", "6.1.0"),