treewide: fixup breakage due to absolute compiler path

Some packages just can't handle them #44767.  It was tempting to try
to abstract this in some way, but I didn't do that ATM.

pkgs/games/warmux/default.nix

@@ -19,6 +19,11 @@ stdenv.mkDerivation rec {
       gettext intltool libtool perl
     ];
 
+  preConfigure = ''
+    CC=${stdenv.cc.targetPrefix}cc
+    CXX=${stdenv.cc.targetPrefix}c++
+  '';
+
   configureFlagsArray = ("CFLAGS=-include ${zlib.dev}/include/zlib.h");
 
   patches = [ ./gcc-fix.patch ];