In commit 518a2f1925c3 ("dma-mapping: zero memory returned from
dma_alloc_*"), dma_alloc_coherent has already zeroed the memory. So
memset is not needed.
Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>