As dmac is already resolved in kernel while creating AH, there is no
need to repeat the resolving in userspace. Prioritizes getting dmac
from kernel driver, unless kernel driver didn't response one.
Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
Signed-off-by: Ran Zhou <zhouran10@h-partners.com>
