If the sock belongs to a polling group, we already have the mechanism to do the write/flush work. Change-Id: Ic15660717f4e83d873ec9f642ababd7fd9cda5eb Signed-off-by: Ziye Yang <ziye.yang@intel.com> Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/5442 Community-CI: Mellanox Build Bot Tested-by: SPDK CI Jenkins <sys_sgci@intel.com> Reviewed-by: Changpeng Liu <changpeng.liu@intel.com> Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>