This allows to enable HPD interrupts for individual pins to only receive
hotplug events from lines which are connected and working.

v2: Restructured initailization of const arrays following a suggstion
    by Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Egbert Eich <eich@suse.de>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>