ASoC: Initial WM8962 IRQ support

Provide an initial hookup for interrupts on the WM8962. Currently we simply
report error status via log messages if an IRQ is provided for the device.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/include/sound/wm8962.h b/include/sound/wm8962.h
index f70258e..cc32aff 100644
--- a/include/sound/wm8962.h
+++ b/include/sound/wm8962.h
@@ -17,6 +17,8 @@
 struct wm8962_pdata {
 	u32 gpio_init[WM8962_MAX_GPIO];
 
+	bool irq_active_low;
+
 	bool spk_mono;   /* Speaker outputs tied together as mono */
 };