Anubis cannot be built with a recent gdbm

[Maxim Cournoyer]

Hello,

When trying to build Anubis with gdbm support (using gdbm version
1.18.1), the compilation fails with errors such as:

gdbm.c:212:1: error: conflicting types for ‘gdbm_db_strerror’

By the way, is there a reason why this project isn't accessible via
Debbugs?  It'd be much easier tracking existing issues if it was.

Thanks,

Maxim