acm: Code restructuring on domain create/destroy.

acm: Code restructuring on domain create/destroy.

When a domain is created, the function acm_domain_create() in
domain_create() is called that does what previously the pre- and
post_domain_create functions were doing. Similarly there's a function
acm_domain_destroy() in domain_kill() that reverts changes to state
when destroying a domain. There's no more separate initialization
necessary for domain-0, but domain_create takes one more parameter,
the ssidref. It is usually passed through the hypercall when a domain
is created.

Signed-off-by: Stefan Berger <stefanb@us.ibm.com>