[Libvirt-cim] Various fixes revealed by Coverity scan report

[Eduardo Lima (Etrunko)]

Hi all,

The cool RedHat folks were kind enough to share a recent report generated by
Coverity which exposes a lot of potential errors on libvirt-cim code.

https://bugzilla.redhat.com/show_bug.cgi?id=728245#c8
https://bugzilla.redhat.com/attachment.cgi?id=530435

I went through each one of them and fixed all of them that I considered it
actually make sense to fix. There are a few false positives that were ignored.
The result is this series of patches following.

Finally, I have ran the cimtests with all these applied and they work as
expected.

Best regards,

--
Eduardo de Barros Lima
Software Engineer, Open Virtualization
Linux Technology Center - IBM/Brazil
eblima at br.ibm.com