net: hns3: void array out of bound when loop tnl_num

In the Linux kernel, the following vulnerability has been resolved: net: hns3: void array out of bound when loop tnl_num When query reg inf of SSU, it loops tnl_num times. However, tnl_num comes from hardware and the length of array is a fixed value. To void array out of bound, make sure the loop time is not greater than the length of array