logd: Add LogUtils.h

Move prototypes from LogBufferElement.h to LogUtils.h

Change-Id: I55e42e17e6c997e35b2b78b87fd2f84f8f393282
diff --git a/logd/main.cpp b/logd/main.cpp
index cbdf0b6..f0a39b4 100644
--- a/logd/main.cpp
+++ b/logd/main.cpp
@@ -47,6 +47,7 @@
 #include "LogListener.h"
 #include "LogAudit.h"
 #include "LogKlog.h"
+#include "LogUtils.h"
 
 #define KMSG_PRIORITY(PRI)                            \
     '<',                                              \