drm/i915: Fix noatomic crtc disabling, v2.

This fixes the breakage caused by

commit eddfcbcdc27fbecb33bff098967bbdd7ca75bfa6
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date:   Mon Jun 15 12:33:53 2015 +0200

    drm/i915: Update less state during modeset.

    No need to repeatedly call update_watermarks, or update_fbc.
    Down to a single call to update_watermarks in .crtc_enable

    Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
    Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
    Tested-by(IVB): Matt Roper <matthew.d.roper@intel.com>
    Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Add missing shared dpll disable to the noatomic disable function.

This function will be replaced by its atomic counterpart soon.

Changes since v1:
- intel_crtc->active and watermarks are fixed by a patch from
  Patrik Jakobsson

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -6214,6 +6214,7 @@ static void intel_crtc_disable_noatomic(struct drm_crtc *crtc)
 
 	intel_crtc_disable_planes(crtc, crtc->state->plane_mask);
 	dev_priv->display.crtc_disable(crtc);
+	intel_disable_shared_dpll(intel_crtc);
 
 	domains = intel_crtc->enabled_power_domains;
 	for_each_power_domain(domain, domains)