Make pbtombstone a host tool.

This is preparation for the next patch, which adds host-side
symbolization capabilities to pbtombstone.

Bug: 328531087
Change-Id: Id5813ae6b121af784643b1ed76084e49fdca118b
diff --git a/debuggerd/libdebuggerd/utility.cpp b/debuggerd/libdebuggerd/utility.cpp
index 742ac7c..b5a93b7 100644
--- a/debuggerd/libdebuggerd/utility.cpp
+++ b/debuggerd/libdebuggerd/utility.cpp
@@ -17,6 +17,7 @@
 #define LOG_TAG "DEBUG"
 
 #include "libdebuggerd/utility.h"
+#include "libdebuggerd/utility_host.h"
 
 #include <errno.h>
 #include <signal.h>