8145083: Use semaphore instead of mutex for synchronization of Unified Logging configuration

Reviewed-by: dholmes, kbarrett, mgronlun

hotspot/src/share/vm/logging/log.cpp

@@ -36,7 +36,6 @@ void Test_log_length() {
   remove("loglengthoutput.txt");
 
   // Write long message to output file
-  MutexLocker ml(LogConfiguration_lock);
   LogConfiguration::parse_log_arguments("loglengthoutput.txt", "logging=trace",
     NULL, NULL, NULL);
   ResourceMark rm;