ASoC: PXA: Fix jack detection on Zipit Z2

Fix jack detection on Zipit Z2, otherwise it
disables headphones output when jack is connected

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/pxa/z2.c

@@ -104,6 +104,7 @@ static struct snd_soc_jack_gpio hs_jack_gpios[] = {
 		.name		= "hsdet-gpio",
 		.report		= SND_JACK_HEADSET,
 		.debounce_time	= 200,
+		.invert		= 1,
 	},
 };