Updated expat packages fix security vulnerabilities

Updated expat packages fix security vulnerabilities: An issue was introduced when CVE-2012-0876 was addressed. Stefan Sørensen discovered that the use of the function XML_Parse() seeds the random number generator generating repeated outputs for rand() calls (CVE-2012-6702). Due to an incomplete solution for CVE-2012-0876, the parser poorly seeds the random number generator allowing an attacker to cause a denial of service (CPU consumption) via an XML file with crafted identifiers (CVE-2016-5300).