dma_alloc_coherent takes care of zeroing allocated memory
Suggested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>