[libvirt] [PATCH 0/3] Make access to virCapsPtr threadsafe in QEMU

The 'caps' object in virQEMUDriverPtr can be re-created at any time, so currently any access is protected by the 'driver' lock. This is really bad for concurrency, since the 'caps' object is used all over the place. This series refactors the QEMU driver so that this is a reference counted object. The lock is now only required while obtaining a reference to the object. This will let us remove the QEMU driver lock from much code in the future.