firewire: build fix

alpha:

drivers/firewire/fw-ohci.c: In function 'ar_context_tasklet':
drivers/firewire/fw-ohci.c:266: warning: implicit declaration of function 'dma_sync_single_for_device'
drivers/firewire/fw-ohci.c:267: error: 'DMA_TO_DEVICE' undeclared (first use in this function)
drivers/firewire/fw-ohci.c:267: error: (Each undeclared identifier is reported only once
drivers/firewire/fw-ohci.c:267: error: for each function it appears in.)
drivers/firewire/fw-ohci.c: In function 'ar_context_init':
drivers/firewire/fw-ohci.c:282: warning: implicit declaration of function 'dma_map_single'
drivers/firewire/fw-ohci.c:283: error: 'DMA_TO_DEVICE' undeclared (first use in this function)
drivers/firewire/fw-ohci.c:293: error: 'DMA_FROM_DEVICE' undeclared (first use in this function)
etc.

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>