```
net/htpdate: Fix the service script
For some reason the PID written to the pidfile by htpdate does not match its
actual PID, which renders the standard PID-handling mechanism of rc.subr(8)
useless.
As a solution, depend only on the process name to figure out the PID of the
running process.
NB: the old pidfile has to be removed before starting htpdate. Otherwise, the
program complains about the pidfile already existing (which htpdate interprets
as another instance of htpdate already running).
In response to this mailing list thread:
https://lists.freebsd.org/pipermail/freebsd-rc/2019-August/004047.html
```