net/freeipa-server: Respect PREFIX and fix service restarts

The patches hardcoded /usr/local. They now carry %%PREFIX%% for this port's
own files and %%LOCALBASE%% for what other ports install, substituted in
post-patch.

Two restart fixes: the rc script passes --ignore-service-failures on restart
as it already does on start, so one failing service no longer takes the
Directory Server down with it, and FreeBSDService re-checks a service after a
failed rc action instead of trusting a status check that raced the pidfile.

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