Add XBMC version 11

Commit ecf27c8ce8144e5a2fbeee5489dcf93a24760f5b changes utils.sh in build-support, and so a lot of things get recompiled.
That diff was mentioned in the mailing list several months ago but wasn't merged in.
This time XBMC's configure won't work without it.

Nix-expression for XBMC was tested (by hand that is) on a x86_64 machine with all possible *Support flags combinations. Runs fine on a ASRock ION 330 HTPC.