As suggested by Cole, this patch uses the domain capabilities to
validate the supported video model types. This allows us to remove the
model type validation from qemu_process.c and qemu_domain.c and
consolidates it all in a single place that will automatically adjust
when new domain capabilities are added.
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Signed-off-by: NJonathon Jongsma <jjongsma@redhat.com>