wayland: disable on avr32

The epoll_create1, timerfd_create and timerfd_settime syscalls are not available
on avr32. Fixes build failures such as the following.

  http://autobuild.buildroot.net/results/43b/43b3df5978782034279604abde8fe5d46c441344/



Signed-off-by: Simon Dawson <spdawson@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>