Allow passing of '--target-list=' to configure to request that
all targets are to be disabled. This allows for doing a very
fast tools-only build of things like qemu-img, qemu-io, qemu-nbd.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>