libdwarf: add zlib to buildInputs

Without this, `dwarfdump` gives errors when trying to show debug information
with compressed dwarf sections.

pkgs/development/libraries/libdwarf/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, libelf }:
+{ stdenv, fetchurl, libelf, zlib }:
 
 let
   version = "20181024";
@@ -24,7 +24,7 @@ in rec {
     preConfigure = ''
       cd libdwarf
     '';
-    buildInputs = [ libelf ];
+    buildInputs = [ libelf zlib ];
 
     installPhase = ''
       mkdir -p $out/lib $out/include