dev: pmic: pm8x41: Add support to read pmic revision id.

Change-Id: I0aad9bfdb186c9af338fbb11890d21a72b637ed3
diff --git a/dev/pmic/pm8x41/include/pm8x41.h b/dev/pmic/pm8x41/include/pm8x41.h
index c199011..eada6cc 100644
--- a/dev/pmic/pm8x41/include/pm8x41.h
+++ b/dev/pmic/pm8x41/include/pm8x41.h
@@ -61,6 +61,8 @@
 
 #define PON_PSHOLD_WARM_RESET   0x1
 
+#define PMIC_VERSION_V2         1
+
 struct pm8x41_gpio {
 	int direction;
 	int output_buffer;
@@ -82,6 +84,7 @@
 void pm8x41_reset_configure(uint8_t);
 int pm8x41_ldo_set_voltage(const char *, uint32_t);
 int pm8x41_ldo_control(const char *, uint8_t);
+uint8_t pm8x41_get_pmic_rev();
 
 struct pm8x41_ldo {
 	const char *name;