The driver does not check value returned by dma_map_page. The patch
fixes this.

v2: Removed the bugfix for non-bug ;-) (thanks Sathya)
Signed-off-by: NIvan Vecera <ivecera@redhat.com>
Acked-by: NSathya Perla <Sathya.perla@emulex.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>