Updated x11-server packages fix security vulnerabilities

The handler for the XkbSetNames request does not validate the request length before accessing its contents (CVE-2020-14345). An integer underflow exists in the handler for the XIChangeHierarchy request (CVE-2020-14346). An integer underflow exist in the handler for the XkbSelectEvents request (CVE-2020-14361). An integer underflow exist in the handler for the CreateRegister request of the X record extension (CVE-2020-14362). The x11-server package has been updated to version 1.20.9, fixing these issues and other bugs.