firewire: build fix 2

ia64:

drivers/firewire/fw-sbp2.c: In function `sbp2_command_orb_map_scatterlist':
drivers/firewire/fw-sbp2.c:826: warning: implicit declaration of function `sg_dma_len'
drivers/firewire/fw-sbp2.c:828: warning: implicit declaration of function `sg_dma_address'
drivers/firewire/fw-sbp2.c:837: error: invalid use of undefined type `struct scatterlist'
drivers/firewire/fw-sbp2.c:838: error: invalid use of undefined type `struct scatterlist'

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>