irc/anope: unbreak with libc++ 8

In file included from src/access.cpp:12:
In file included from include/service.h:15:
In file included from include/services.h:22:
In file included from /usr/include/c++/v1/stdexcept:46:
In file included from /usr/include/c++/v1/exception:81:
In file included from /usr/include/c++/v1/cstddef:38:
include/version:1:1: error: expected unqualified-id
<U+007F>ELF<U+0002><U+0001><U+0001> <U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><U+0002><U+0000>><U+0000><U+0001><U+0000><U+0000><U+0000><U+0000>P <U+0000><U+0000><U+0000><U+0000><U+0000>@<U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><F0>"<U+0001><U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><U+0000><U+0000>@<U+0000>8
^

PR: 236192
Approved by: portmgr blanket