Factor out smram/pam logic for use by other chipsets, namely q35
at this point.

Note: Should be factored out into a generic North Bridge Class.

[jbaron@redhat.com: changes for updated memory API]
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NJason Baron <jbaron@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>