MDEV-29847: Wrong warning on rlimit capping of max_open_files (#2315)

Per the code my_set_max_open_files 3 lines earlier, we attempt to set the nofile (number of open files), rlimit to max_open_files. We should use this in the warning because wanted_files may not be the number.

Author: grooverdan

sql/mysqld.cc

@@ -4580,8 +4580,8 @@ static int init_common_variables()
  files= my_set_max_open_files(max_open_files);
  SYSVAR_AUTOSIZE_IF_CHANGED(open_files_limit, files, ulong);
 
- if (files < wanted_files && global_system_variables.log_warnings)
- sql_print_warning("Could not increase number of max_open_files to more than %u (request: %u)", files, wanted_files);
+ if (files < max_open_files && global_system_variables.log_warnings)
+ sql_print_warning("Could not increase number of max_open_files to more than %u (request: %u)", files, max_open_files);
 
  /* If we required too much tc_instances than we reduce */
  SYSVAR_AUTOSIZE_IF_CHANGED(tc_instances,