i915: fix intel graphics suspend breakage due to resume/lid event confusion

In commit c1c7af60 ("drm/i915: force
mode set at lid open time") the intel graphics driver was taught to
restore the LVDS mode on lid open.

That caused problems with interaction with the suspend/resume code,
which commonly runs at the same time (suspend is often caused by the lid
close event, while lid open is commonly a resume event), which was
worked around with in commit 06891e27
("drm/i915: fix suspend/resume breakage in lid notifier").

However, in the meantime the lid event code had also grown a user event
notifier (commit 06324194: "drm/i915:
generate a KMS uevent at lid open/close time"), and now _that_ causes
problems with suspend/resume and some versions of Xorg reacting to those
uevents by setting the mode.

So this effectively reverts that commit 06324194

, and makes the lid
open protection logic against suspend/resume more explicit.  This fixes
at least one laptop. See

	http://bugzilla.kernel.org/show_bug.cgi?id=14484

for more details.

Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Riccardo Magliocchetti <riccardo.magliocchetti@gmail.com>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>