logd: Add LogUtils.h

Move prototypes from LogBufferElement.h to LogUtils.h

Change-Id: I55e42e17e6c997e35b2b78b87fd2f84f8f393282
diff --git a/logd/LogStatistics.h b/logd/LogStatistics.h
index 61000d2..20e630e 100644
--- a/logd/LogStatistics.h
+++ b/logd/LogStatistics.h
@@ -26,6 +26,7 @@
 #include <log/log.h>
 
 #include "LogBufferElement.h"
+#include "LogUtils.h"
 
 #define log_id_for_each(i) \
     for (log_id_t i = LOG_ID_MIN; i < LOG_ID_MAX; i = (log_id_t) (i + 1))