EMC voltage for Mariko; Fix #60; Show battery & voltage info in overlay on Erista

- From previous analysis, EMC voltage is set before AMS loads on Mariko, and will not be set again or changed afterwards.

- sys-clk-OC will take care of setting emc voltage on Mariko once it loads.

- OS will not hang at boot as it always boots with EMC @ 1600 MHz.

Source/sys-clk-OC/common/include/sysclk.h

@@ -11,6 +11,7 @@
 #pragma once
 
 #ifdef __cplusplus
+#include "cpp_util.hpp"
 extern "C" {
 #endif