Test osmo-ggsn master with the Linux kernel built from main of
<a href="https://git.kernel.org/pub/scm/linux/kernel/git/pablo/gtp.git/">pablo/gtp.git</a>.
<br>
This is a temporary job, to be removed once the IPv6 related GTP
patches are upstreamed (OS#1952).
<!-- Managed by Jenkins Job Builder -->