unzip: cc-wrapper has been fixed so don't need to be so clever

pkgs/tools/archivers/unzip/default.nix

···
 
   makefile = "unix/Makefile";
 
-  ${"NIX_${stdenv.cc.infixSalt_}LDFLAGS"} = [ "-lbz2" ] ++ stdenv.lib.optional enableNLS "-lnatspec";
+  NIX_LDFLAGS = [ "-lbz2" ] ++ stdenv.lib.optional enableNLS "-lnatspec";
 
   buildFlags = "generic D_USE_BZ2=-DUSE_BZIP2 L_BZ2=-lbz2";