ejabberd_logger: Avoid excessive stat calls

By default, the logger_std_h module shipped with OTP 21.0 and newer
reads the log file information prior to each and every write operation.
This is done to play well with external log rotation tools.

In order to minimize the performance penalty in situations where the log
file is flooded, configure logger_std_h to skip reading the file
information as long as no more than one second has passed since it was
last read.

src/ejabberd_logger.erl

@@ -260,6 +260,7 @@ start(Level) ->
     Config = #{max_no_bytes => LogRotateSize,
 	       max_no_files => LogRotateCount,
 	       filesync_repeat_interval => no_repeat,
+	       file_check => 1000,
 	       sync_mode_qlen => 1000,
 	       drop_mode_qlen => 1000,
 	       flush_qlen => 5000},