atk: remove useless configuration options

ATK is not directly related to X11, and the --with-x, --x-includes,
--x-libraries and --without-x options do not exist.

The --disable-glibtest was duplicated, and is therefore still passed
to the configuration options.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>