Revert "drm/i915: Don't enable pipe/plane/VCO early (wait for DPMS on)."

This reverts commit cfecde435dda78248d6fcdc424bed68d5db6be0b, since it
seems to cause some systems to not come up with any video output at all
(or video that only comes on when X starts up).

Fixes bugzilla:

    http://bugzilla.kernel.org/show_bug.cgi?id=16163

Reported-and-tested-by: David John <davidjon@xenontk.org>
Tested-by: Nick Bowler <nbowler@elliptictech.com>
Acked-by: Carl Worth <cworth@cworth.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>