Log variables moved to log_manager.h

The log manager variables lm_enabled_log_files_bitmask, log_ses_count
and tls_log_info that earlier were declared separately in every
c-file are now declared in the log_manager.h header.

server/core/adminusers.c

@@ -30,10 +30,6 @@
 #include <log_manager.h>
 #include <gwdirs.h>
 #include <sys/stat.h>
-/** Defined in log_manager.cc */
-extern int            lm_enabled_logfiles_bitmask;
-extern size_t         log_ses_count[];
-extern __thread log_info_t tls_log_info;
 
 /**
  * @file adminusers.c - Administration user account management