dev: pmic: Add power key detection support

Add one function: pm8x41_get_pwrkey_is_pressed to detect if
power key is pressed or not.

Change-Id: Id86070e4c03e82d73cf0e6e1912809cb83ad2236
diff --git a/dev/pmic/pm8x41/include/pm8x41_hw.h b/dev/pmic/pm8x41/include/pm8x41_hw.h
index c696ef6..a1c2e6d 100644
--- a/dev/pmic/pm8x41/include/pm8x41_hw.h
+++ b/dev/pmic/pm8x41/include/pm8x41_hw.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2014, The Linux Foundation. All rights reserved.
 
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
@@ -82,6 +82,7 @@
 
 /* PON Peripheral register bit values */
 #define RESIN_ON_INT_BIT                      1
+#define KPDPWR_ON_INT_BIT                     0
 #define RESIN_BARK_INT_BIT                    4
 #define S2_RESET_EN_BIT                       7