drm/udl: rip out set_need_resched

This very much looks like copypasta from drm/i915's fault handler.
It was used there to duct-tape over issues around gpu reset handling.

Since that can't ever happen for udl and there's seemingly no other
reason for this just drop it.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>