net: hns3: Fix desc num set to default when setting channel

net: hns3: Fix desc num set to default when setting channel

BugLink: https://bugs.launchpad.net/bugs/1793404
When user set the channel num using "ethtool -L ethX", the desc num
of BD will set to default value, which will cause desc num set by
user lost problem.

This patch fixes it by restoring the desc num set by user when setting
channel num.

Fixes: 09f2af6405b8 ("net: hns3: add support to modify tqps number")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 128b900de7df567ca7ca063bf5da4ed0f357db8c)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>