firewire: ohci: fix regression with VIA VT6315, disable MSI

"VIA Technologies, Inc. VT6315 Series Firewire Controller [1106:3403]"
does not generate any interrupts if Message Signaled Interrupts were
enabled.  This is a regression since kernel 2.6.36 in which MSI support
was added to firewire-ohci.  Hence blacklist MSI on all VIA controllers.

Reported-by: Robin Cook <rcook@wyrms.net>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: <stable@kernel.org> # 2.6.36.y