Zabbix

...G...... [ZBX-21703] added mutex between perfmon collector and exporter

Merge in ZBX/zabbix from feature/ZBX-21703-6.0 to release/6.0

* commit '56b6f3bc8645df1a24578b5274f4373902ee49ab':
  ...G...... [ZBX-21703] updated with changes from release 6.4
  ...G...... [ZBX-21703] added mutex between collector and exporter