PCI: disable MSI on VIA K8M800

commit 549e15611b4ac1de51ef0e0a79c2704f50a638a2 upstream.

MSI delivery from on-board ahci controller doesn't work on K8M800.  At
this point, it's unclear whether the culprit is with the ahci
controller or the host bridge.  Given the track record and considering
the rather minimal impact of MSI, disabling it seems reasonable.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Rainer Hurtado Navarro <publio.escipion.el.africano@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>