This adds a simple log rotation extension to every networking service that
specifies a #:log-file in its Shepherd service, which should prevent some logs
from accumulating indefinitely.
* gnu/services/networking.scm (%ntp-log-rotation): New variable.
(ntp-service-type): Extend 'rottlog-service-type'.
(openntpd-shepherd-service): Change #:log-file argument to "/var/log/ntpd.log".
(openntpd-service-type): Extend 'rottlog-service-type'.
(%tor-log-rotation): New variable.
(tor-service-type): Extend 'rottlog-service-type'.
(%connman-log-rotation): New variable.
(connman-service-type): Extend 'rottlog-service-type'.
(%hostapd-log-rotation): New variable.
(hostapd-service-type): Extend 'rottlog-service-type'.
(%pagekite-log-rotation): New variable.
(pagekite-service-type): Extend 'rottlog-service-type'.
(%yggdrasil-log-rotation): New variable.
(yggdrasil-service-type): Extend 'rottlog-service-type'.
(%ipfs-log-rotation): New variable.
(ipfs-service-type): Extend 'rottlog-service-type'.
(%keepalived-log-rotation): New variable.
(keepalived-service-type): Extend 'rottlog-service-type'.
Signed-off-by: Ludovic Courtès <ludo@gnu.org>