net: hns3: check reset pending after FLR prepare

If there is a PF reset pending before FLR prepare, FLR's
preparatory work will not fail, but the FLR rebuild procedure
will fail for this pending. So this PF reset pending should
be handled in the FLR preparatory.

Fixes: 8627bded ("net: hns3: refactor the precedure of PF FLR")
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>