[PATCH] serverworks: add support for new southbridge IDE

BCM5785 (HT1000) is a Opteron Southbridge from Serverworks/Broadcom that
incorporates a single channel ATA100 IDE controller that is functionally
identical to the Serverworks CSB6 IDE controller.  This patch adds support
for the new PCI device ID and also the support for this controller.

Signed-off-by: Narendra Sankar <nsankar@broadcom.com>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>