[libvirt] [PATCHv2 0/3] util: capabilities detection for dnsmasq

This patch series resolves the libvirt part of CVE 2012-3411: https://bugzilla.redhat.com/show_bug.cgi?id=833033 Further details are in PATCH 3/3. The changes from V1 are all in PATCH 1/3 (resulting from Doug Goldstein's review): 1) rework dnsmasqCapsRefresh() to create a new caps object if it's given a NULL object (function now gets dnsmasqCapsPtr* instead of dnsmasCapsPtr). This makes it possible to recover properly if dnsmasq is installed after libvirtd has already been started. 2) Add the following before each run of dnsmasq: virCommandAddEnvPassCommon(cmd); virCommandClearCaps(cmd); 3) Fixed a missing space after comma :-)