[SCSI] use kmem_cache_zalloc instead of kmem_cache_alloc/memset

Signed-off-by: Wei Yongjun <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/scsi.c

···
 {
 	struct scsi_cmnd *cmd;
 
-	cmd = kmem_cache_alloc(pool->cmd_slab, gfp_mask | pool->gfp_mask);
+	cmd = kmem_cache_zalloc(pool->cmd_slab, gfp_mask | pool->gfp_mask);
 	if (!cmd)
 		return NULL;
-
-	memset(cmd, 0, sizeof(*cmd));
 
 	cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab,
 					     gfp_mask | pool->gfp_mask);