Security update for libxml2

Open Source Vulnerabilities SUSE-SU-2016:0030-1

This update fixes the following security issues: * CVE-2015-1819 Enforce the reader to run in constant memory [bnc#928193] * CVE-2015-7941 Fix out of bound read with crafted xml input by stopping parsing on entities boundaries errors [bnc#951734] * CVE-2015-7942 Fix another variation of overflow in Conditional sections [bnc#951735] * CVE-2015-8241 Avoid extra processing of MarkupDecl when EOF [bnc#956018] * CVE-2015-8242 Buffer overead with HTML parser in push mode [bnc#956021] * CVE-2015-8317 Return if the encoding declaration is broken or encoding conversion failed [bnc#956260] * CVE-2015-5312 Fix another entity expansion issue [bnc#957105] * CVE-2015-7497 Avoid an heap buffer overflow in xmlDictComputeFastQKey [bnc#957106] * CVE-2015-7498 Processes entities after encoding conversion failures [bnc#957107] * CVE-2015-7499 Add xmlHaltParser() to stop the parser / Detect incoherency on GROW [bnc#957109] * CVE-2015-7500 Fix memory access error due to incorrect entities boundaries [bnc#957110]