ASoC: twl6040: Enable plug detection interrupts

Enable plug detection interrupt mask in order to get headset
PLUGINT/UNPLUGINT interrupts.

Signed-off-by: Misael Lopez Cruz <misael.lopez@ti.com>
Signed-off-by: Margarita Olaya Cabrera <magi.olaya@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/sound/soc/codecs/twl6040.h b/sound/soc/codecs/twl6040.h
index 67396f6..23aeed0 100644
--- a/sound/soc/codecs/twl6040.h
+++ b/sound/soc/codecs/twl6040.h
@@ -79,6 +79,7 @@
 
 /* INTMR (0x04) fields */
 
+#define TWL6040_PLUGMSK			0x02
 #define TWL6040_READYMSK		0x40
 #define TWL6040_ALLINT_MSK		0x7B