Made more libraries cross compile. fontconfig, libxcb, bzip2, libdrm, zlib...

I was trying to cross compile SDL. Many dependencies work, but I ended seeing
libX11 not ready for cross compilation. Other xorg libraries cross-compile
well. libX11 may need a small patch. The problem is the usual "configure test
cannot be run in cross compilation", so the configure script halts.

I made the pkgconfig expression always return buildDrv, as I think it rarely
will be needed as buildInput. So to avoid rewriting all its mentions to use
it as buildNativeInput, I prefered this small change.


svn path=/nixpkgs/branches/stdenv-updates/; revision=18500

pkgs/development/libraries/libdrm/default.nix

@@ -10,6 +10,13 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ pkgconfig libpthreadstubs ];
 
+  preConfigure = ''
+    # General case: non intel.
+    if test -n "$crossConfig"; then
+      configureFlags="$configureFlags --disable-intel";
+    fi
+  '';
+
   meta = {
     homepage = http://dri.freedesktop.org/libdrm/;
     description = "Library for accessing the kernel's Direct Rendering Manager";