Turns out the only thing we use NO_HW_ONLY_EXTS for is to check whether
or not we're building inside the Xorg DDX. Replace it with an
XorgLoader test instead, and remove all its users.
Signed-off-by: Daniel Stone <daniel@fooishbar.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>