Improve init bootcharting.

Most notably, there's no longer any need to guess an end time.

Bug: http://b/23478578
Bug: http://b/33450491
Test: rebooted with bootcharting on/off
Change-Id: Icb7d6859581da5526d77dfc5aa4d57c9bfbfd7e2
diff --git a/init/bootchart.h b/init/bootchart.h
index 47eda7a..1e8d0f8 100644
--- a/init/bootchart.h
+++ b/init/bootchart.h
@@ -20,7 +20,7 @@
 #include <string>
 #include <vector>
 
-int do_bootchart_init(const std::vector<std::string>& args);
+int do_bootchart(const std::vector<std::string>& args);
 void bootchart_sample(int* timeout);
 
 #endif /* _BOOTCHART_H */