net: hns3: Fix potential null pointer defererence of null ae_dev

mainline inclusion
from mainline-v5.13-rc1
commit d0494135f94c7ab5a9cf7a9094fbb233275c7ba6
category: bugfix
bugzilla: NA
CVE: NA

----------------------------

The reset_prepare and reset_done calls have a null pointer check
on ae_dev however ae_dev is being dereferenced via the call to
ns3_is_phys_func with the ae->pdev argument. Fix this by performing
a null pointer check on ae_dev and hence short-circuiting the
dereference to ae_dev on the call to ns3_is_phys_func.

Addresses-Coverity: ("Dereference before null check")
Fixes: 715c58e94f0d ("net: hns3: add suspend and resume pm_ops")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Reviewed-by: li yongxin <liyongxin1@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>