sanitytest: Fix libvirtError class handling for Python 2.4
sanitytest: Fix libvirtError class handling for Python 2.4

The Exception class hiearchy in Python 2.4 reports different
data types than in later Python versions. As a result the
type(libvirt.libvirtError) does not return 'type'. We just
special case handling of this class.

Signed-off-by: Daniel P. Berrange <bb938cf255e055ff3507f2627d214e8e62118fcf@redhat.com>

libvirt/libvirt-python,libvirt/libvirt-python,libvirt/libvirt-python