• net-p2p/bitcoin: fix path error in startup script files/bitcoin.in also removes reliance on unnecessary cli script.

• net-p2p/bitcoin-daemon: create the user/group for the daemon to use also install a sample configuration file.

With these two patches a "pkg install bitcoin-daemon" followed by "service
start bitcoind" will be sufficient to run as a non-privileged user and
automatically connect to bitcoin live network; using /var/db/bitcoin to store
blockchain data.

PR: 215059
Submitted by: Christopher Hall <hsw@bitmark.com>
Approved by: <robbak@robbak.com> (maintainer)