Run test suite as part of RPM build process

Run test suite as part of RPM build process

To ensure that patches in the RPM don't break any functionality
it is neccessary to run the test suites during build. It currently
has 3 tests disabled

 - daemon-conf: this is totally broken, since it relies on
   being able to resolve the 'libvirt' group & being able to
   resolve hostnames at daemon startup. This isn't possible
   in a mock build root
 - seclabeltest: fails to initialize selinux in the mock
   build root. Possibly fixable
 - nodeinfotest: broken on s390 + ppc - this is a real bug

* libvirt.spec.in: Add a %check section, with 3 tests
   temporarily disabled