update the logging example to reflect the current default level

Summary:
D8941725 changed the default log level from WARNING to INFO.  This updates the
comments in the example logging program to reflect that.

Reviewed By: yfeldblum

Differential Revision: D21332969

fbshipit-source-id: 88b206bf4dc891d8868a34ea02d91cc79b7c5c48

folly/logging/example/main.cpp

@@ -37,8 +37,8 @@ FOLLY_INIT_LOGGING_CONFIG(
 int main(int argc, char* argv[]) {
   // Using log macros before calling folly::initLogging() will use the default
   // log settings defined by folly::initializeLoggerDB().  The default behavior
-  // is to log WARNING+ messages to stderr.
-  XLOG(INFO) << "log messages less than WARNING will be ignored";
+  // is to log INFO+ messages to stderr.
+  XLOG(DBG) << "log messages less than INFO will be ignored before initLogging";
   XLOG(ERR) << "error messages before initLogging() will be logged to stderr";
 
   // folly::Init() will automatically initialize the logging settings based on