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

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

This reverts commit 2e212c0769200350284a0f1bf80b33ce652a4e82, 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>