Removing coreutils_real from release-cross.

It had to be 'coreutils' instead, but I don't think they cross-build. They
cross-build only in stdenv-updates I tihnk.

svn path=/nixpkgs/trunk/; revision=23774

pkgs/top-level/release-cross.nix

···
   basicHostDrv = {
     bison.hostDrv = nativePlatforms;
     busybox.hostDrv = nativePlatforms;
-    coreutils_real.hostDrv = nativePlatforms;
     dropbear.hostDrv = nativePlatforms;
     tightvnc.hostDrv = nativePlatforms;
     #openoffice.hostDrv = nativePlatforms;