net: hns: Adjust the SBM module buffer threshold

net: hns: Adjust the SBM module buffer threshold

BugLink: https://bugs.launchpad.net/bugs/1696031
HNS needs SMB Buffers to store at least two packets after sending
pause frame because of the link delay. The MTU of HNS is 9728. As
the processor user manual described, the SBM buffer threshold should
be modified.

Reported-by: Ping Zhang <zhangping5@huawei.com>
Signed-off-by: Kejian Yan <yankejian@huawei.com>
Reviewed-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 76b588bc523bee796834ebd319f6a71ad3eddbae)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>