The two options are separate, and some platforms (e.g. arm pxa)
have ISA slots but no ISA dma controller, so they cannot build
drivers using the DMA API functions.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>