Introduce VLANClientState::cleanup() (Mark McLoughlin)

We're currently leaking memory and file descriptors on device
hot-unplug.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7150 c046a42c-6fe2-441c-8c8c-71466251a162
