[ Upstream commit 26fd962bde0b15e54234fe762d86bc0349df1de4 ]

niu_pci_eeprom_read() may fail, so we should check its return value
before using the read data.
Signed-off-by: NKangjie Lu <kjlu@umn.edu>
Acked-by: NShannon Nelson <shannon.lee.nelson@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>