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

This reverts commit cfecde43, 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>