stable/11: Bump FreeBSD_Version for recent rc ${name}_limits bits

Some ports had their own interpretation of _limits that conflicted with the
new definition as of r328331. r331880 was an MFC of this commit to
stable/11. Bump FreeBSD_Version in stable/11 following r331880 so that ports
can do the right thing.

This is a direct commit to stable/11

Reported by: 0mp