The previous patch did not compile cleanly on all architectures so
here's a fixed one which #includes <linux/dma-mapping.h>.

Use the DMA_{64,32}BIT_MASK constants from dma-mapping.h when calling
pci_set_dma_mask() or pci_set_consistent_dma_mask()
This patch includes dma-mapping.h explicitly because it caused errors
on some architectures otherwise.
See http://marc.theaimsgroup.com/?t=108001993000001&r=1&w=2 for details
Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: Domen Puncer <domen@coderock.org>

diff -puN drivers/scsi/ahci.c~dma_mask-drivers_scsi_ahci drivers/scsi/ahci.c