KVM unittest: avoid leaking QMP connection FDs
KVM unittest: avoid leaking QMP connection FDs

Make sure we close all client and server QMP sockets to avoid
ResourceWarnings.

Signed-off-by: Apollon Oikonomopoulos <ed81ed0a45ccd5c8869bda52e38353a6299ee39e@dmesg.gr>

ganeti/ganeti,mbakke/ganeti,mbakke/ganeti,ganeti/ganeti,mbakke/ganeti,ganeti/ganeti