making wireguard work on RHEL7/etc.

[wireguard at wut.to]

Jason A. Donenfeld wrote:

> Okay, and for the kernel, please give this commit a try:
>
> https://git.zx2c4.com/WireGuard/commit/?id=32e20ef627048ffa7f8cb3567e6b4c639cd42607
>
> Or just run the latest git master.
>

after a quick wg-quick stop / rmmod / insmod / wg-quick start / ping this
seems to work.