drm/i915: Initialize intel_crtc->active

drm/i915: Initialize intel_crtc->active

Fix a regression in the previous regression fix...

In order to turn off the pipes entirely upon the first modeset, we
pretend that BIOS (or earlier module incarnation) left them active.
The first task performed by setup_initial_configuration() is to disable
all pipes and so to avoid skipping that step and so to ensure a known
configuration we need to mark all the crtcs as active.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>