Fix the build for net-mgmt/nagios-check_bacula11
This patch has been committed upstream via
https://www.bacula.org/git/cgit.cgi/bacula/commit/?h=Branch-11.0&id=ef3a7fe40a2aee5e7acb3bf3144bba713c9cf982
(cherry picked from commit 80b2fa6dd4250768bc02483819e9c02f3168c7a8)