AHB DMA is a running on 1/2 of SCLK rate, APB DMA on 1/4. Increasing SCLK
rate results in an increased DMA transfer rate.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-By: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>