Three fixes for xorg FTBFSes

[Daniel Stone <daniel@fooishbar.org>]

Hi,
I've got a patch up on http://people.debian.org/~daniels/ that fixes
three issues with 6.8.2.dfsg.1-1:
	* vars.s390 has _XFREE86_ instead of _XORG_, causing FTBFS of
	  sorts when it attempts to build the debug server -- it trips
	  some nasty breakage in ...
	* libXprintUtil is built unconditionally, even in the debug
	  server, which causes an FTBFS when libXt headers aren't
	  found because you don't have libxt-dev installed and make
	  includes hasn't recursed to lib/Xt; #009 amended to only
	  BuildXPrintLib when !BuildServersOnly, which dirties #600
	  due to offset;
	* when building with linux-libc-headers, <linux/config.h>
	  can't be included from userspace, so 000_stolen_from_drm.diff
	  from Ubuntu is restored, which guards the inclusion with
	  __KERNEL__.

I think these changes should get us to the stage where these weird
architectures fail on MANIFEST checks, rather than during actually
building the package.

.diff.gz, .dsc, and interdiff on the URL above.

Cheers,
Daniel