drm/i915/edp: Increase the T12 delay quirk to 1300ms

For this specific PCI device, the eDP panel requires a higher panel
power cycle delay of 1300ms where the minimum spec requirement of panel
power cycle delay is 500ms. This fix in combination with correct
timestamp at which we get the panel power off time fixes the dP AUX CH
timeouts seen on various IGT tests.

Fixes: c99a259b4b5192ba ("drm/i915/edp: Add a T12 panel delay quirk to fix
DP AUX CH timeouts")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101144
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101518
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507073845-13420-2-git-send-email-manasi.d.navare@intel.com

drivers/gpu/drm/i915/intel_dp.c

@@ -5286,7 +5286,7 @@ intel_dp_init_panel_power_sequencer(struct drm_device *dev,
 	 * seems sufficient to avoid this problem.
 	 */
 	if (dev_priv->quirks & QUIRK_INCREASE_T12_DELAY) {
-		vbt.t11_t12 = max_t(u16, vbt.t11_t12, 900 * 10);
+		vbt.t11_t12 = max_t(u16, vbt.t11_t12, 1300 * 10);
 		DRM_DEBUG_KMS("Increasing T12 panel delay as per the quirk to %d\n",
 			      vbt.t11_t12);
 	}