drm/i915: vlv: fix VGA hotplug after modeset

Since

commit 912d812e84cea8689a2bf3dd13b11dfe191f0f1e
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Oct 11 20:08:23 2012 +0200

    drm/i915/crt: don't set HOTPLUG bits on !PCH

on VLV we don't detect any VGA unplug event after a modeset, since there we
reset the ADPA hotplug bits. Fix it by preserving the hotplug bits on VLV as
well.

Signed-off-by: Imre Deak <imre.deak@intel.com>
[danvet: For consistency use gen >= 5 like in Chris' exact same fix
in intel_crt_reset.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_crt.c

@@ -274,7 +274,7 @@ static void intel_crt_mode_set(struct intel_encoder *encoder)
 	struct drm_display_mode *adjusted_mode = &crtc->config.adjusted_mode;
 	u32 adpa;
 
-	if (HAS_PCH_SPLIT(dev))
+	if (INTEL_INFO(dev)->gen >= 5)
 		adpa = ADPA_HOTPLUG_BITS;
 	else
 		adpa = 0;