Updated x11-server packages fix security vulnerabilities

Eric Sesterhenn discovered that the X.Org X server incorrectly compared MIT cookies. An attacker could possibly use this issue to perform a timing attack and recover the MIT cookie (CVE-2017-2624). It was discovered that the X.Org X server incorrectly handled endianness conversion of certain X events. An attacker able to connect to an X server, either locally or remotely, could use this issue to crash the server, or possibly execute arbitrary code as an administrator (CVE-2017-10971). It was discovered that the X.Org X server incorrectly handled endianness conversion of certain X events. An attacker able to connect to an X server, either locally or remotely, could use this issue to possibly obtain sensitive information (CVE-2017-10972). Use-after-free issue in an unused function in XDM (boo#1025035).