chickenPackages.chickenEggs.mdh: mark as broken due to PCRE

pkgs/development/compilers/chicken/5/overrides.nix

@@ -129,18 +129,8 @@ in
   leveldb = addToBuildInputs pkgs.leveldb;
   magic = addToBuildInputs pkgs.file;
   magic-pipes = addToBuildInputs pkgs.chickenPackages_5.chickenEggs.regex;
-  mdh =
-    old:
-    (addToBuildInputs pkgs.pcre old)
-    // {
-      postPatch = ''
-        substituteInPlace bmgsubs.c \
-          --replace-fail "char   *gotamatch();" "char *gotamatch(char *, int, int (*)(char *, int));" \
-          --replace-fail "int bmg_search(char *, int, int (*)());" "int bmg_search(char *, int, int (*)(char *, int));" \
-          --replace-fail "int	(*action)();" "int (*action)(char *, int);" \
-          --replace-fail "int (*action)();" "int (*action)(char *, int);"
-      '';
-    };
+  # requires PCRE
+  mdh = broken;
   # missing dependency in upstream egg
   mistie = addToPropagatedBuildInputs (with chickenEggs; [ srfi-1 ]);
   mosquitto = addToPropagatedBuildInputs [ pkgs.mosquitto ];