server: fix linking error we need libXrandr
server: fix linking error we need libXrandr

Signed-off-by: Maarten Lankhorst <743c2818a341d71b99ed2b566f9f80c2fc288f93@canonical.com>
Signed-off-by: Peter Hutterer <b9c50af7afa7642f6f854434cda9ffe54ece8b85@who-t.net>

freedesktop-unofficial-mirror/xorg__test__xorg-integration-tests,freedesktop-unofficial-mirror/xorg__test__xorg-integration-tests,freedesktop-unofficial-mirror/xorg__test__xorg-integration-tests