As pointed out by Ján Tomko, "no_memory seems suspicious in the times of
abort()".

As libvirt decided to take the path to not report OOM and simply abort
when it happens, let's get rid of the no_memory labels and simplify the
code around them.
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Signed-off-by: NFabiano Fidêncio <fidencio@redhat.com>