If a xge port just connect with an optical module and no fiber,
it may have a fake link up because there may be interference on
the hardware. This patch adds an anti-shake to avoid the problem.
And the time of anti-shake is base on tests.

Fixes: b917078c ("net: hns: Add ACPI support to check SFP present")
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>