That way, we can make it const as is good kernel style.  We use a separate
indirection for the early console, rather than mugging ops.put_chars.

We rename it hv_ops, too.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>