PCI: Add MSI quirk for ServerWorks HT1000 PCIX bridge.

This is the fix for the following problem:

https://bugzilla.redhat.com/show_bug.cgi?id=227657



The bnx2 device 5706 complains about MSI not working behind a
ServerWorks HT1000 PCIX bridge. An earlier commit to fix the problem:

e3008ded:

"PCI: disable MSI by default on systems with Serverworks HT1000 chips"

was not entirely correct, and has been reverted.

MSI does not work on the PCIX bus because the BIOS did not set the
HT_MSI_FLAGS_ENABLE bit in the HyperTransport MSI capability on the
bridge.  We use the existing quirk_msi_ht_cap() to detect the problem
and disable MSI in all buses behind it.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Cc: Anantha Subramanyam <ananth@broadcom.com>
Cc: Naren Sankar <nsankar@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>