RDMA/hns: Move the location for initializing tmp_len

RDMA/hns: Move the location for initializing tmp_len

BugLink: https://bugs.launchpad.net/bugs/1770974
When posted work request, it need to compute the length of
all sges of every wr and fill it into the msg_len field of
send wqe. Thus, While posting multiple wr,
tmp_len should be reinitialized to zero.

Fixes: 8b9b8d143b46 ("RDMA/hns: Fix the endian problem for hns")
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
(cherry picked from commit 55ba49cbcef37053d973f9a45bc58818c333fe13)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>