drm/i915: Call intel_opregion_notify_encoder in intel_sanitize_encoder, v2.

Normally this is called on a modeset, but the call is missing when
we inherit the mode from the BIOS, so make sure it's called somewhere
in hardware readout.

Changes since v1:
- Unconditionally call intel_opregion_notify_encoder. (Ville)

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180516085038.36785-1-maarten.lankhorst@linux.intel.com
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

drivers/gpu/drm/i915/intel_display.c

@@ -15251,6 +15251,9 @@ static void intel_sanitize_encoder(struct intel_encoder *encoder)
 		connector->base.dpms = DRM_MODE_DPMS_OFF;
 		connector->base.encoder = NULL;
 	}
+
+	/* notify opregion of the sanitized encoder state */
+	intel_opregion_notify_encoder(encoder, connector && has_active_crtc);
 }
 
 void i915_redisable_vga_power_on(struct drm_i915_private *dev_priv)