Replace some 'dma_alloc_coherent+memset' by some quivalent
'dma_zalloc_coherent' in order to reduce code verbosity
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: NChad Dupuis <chad.dupuis@cavium.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>