scripts/systemd/*: delete unused systemd service

This was used in the past when the hotplug
was not working. So, we needed a manager
to spawn our daemons when a new board was
detected

scripts/systemd/etc/systemd/system/bpm-sw.service

-[Unit]
-Description=BPM-SW server
-After=network-online.target
-Wants=network-online.target
-After=media-remote_logs.mount
-Requires=media-remote_logs.mount
-
-[Service]
-EnvironmentFile=/etc/sysconfig/bpm-sw
-ExecStart=/usr/local/bin/dev_mngr -f /usr/local/etc/bpm_sw/bpm_sw.cfg
-WorkingDirectory=/usr/local/bin
-
-[Install]
-WantedBy=multi-user.target