Commit 011c2282 changed the way refcounting on imported dma_bufs
works, and this hadn't been spotted while forward-porting Armada.
Reflect the changes in that commit into the Armada driver.
Reviewed-by: NRob Clark <robdclark@gmail.com>
Reviewed-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>