net: hns3: Fix for mac pause not disable in pfc mode

When pfc pause mode is enable, the mac pause mode need to be
disabled, otherwise the pfc pause packet will not be sent when
congestion happens.

This patch fixes by disabling the mac pause when pfc pause is
enabled.

Fixes: 84844054 ("net: hns3: Add support of TX Scheduler & Shaper to HNS3 driver")
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>