drm/i915: dvo_ch7xxx: fix vsync polarity setting

This fixes a typo which set the wrong vsync and possibly also hsync
polarity for any modes with positive vsync polarity.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/dvo_ch7xxx.c

@@ -307,7 +307,7 @@ static void ch7xxx_mode_set(struct intel_dvo_device *dvo,
 		idf |= CH7xxx_IDF_HSP;
 
 	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
-		idf |= CH7xxx_IDF_HSP;
+		idf |= CH7xxx_IDF_VSP;
 
 	ch7xxx_writeb(dvo, CH7xxx_IDF, idf);
 }