Remove multiple logging implementations.

Change-Id: I7474c29b394f37918a35bba58b2fab58a7be930f
diff --git a/aos/dump_rtprio.cc b/aos/dump_rtprio.cc
index 12000f0..5d9a0b4 100644
--- a/aos/dump_rtprio.cc
+++ b/aos/dump_rtprio.cc
@@ -248,7 +248,7 @@
 
 int main() {
   ::aos::logging::Init();
-  ::aos::logging::AddImplementation(
+  ::aos::logging::SetImplementation(
       new ::aos::logging::StreamLogImplementation(stdout));
 
   const int pid_max = find_pid_max();