This is a semi-incompatible change: gexps previously provided in the
‘schedule’ field will no longer work.
* gnu/services/admin.scm (log-cleanup-mcron-jobs): Remove.
(log-cleanup-shepherd-services): New procedure.
(log-cleanup-service-type): Extend SHEPHERD-ROOT-SERVICE-TYPE instead of
MCRON-SERVICE-TYPE.
* doc/guix.texi (Log Rotation): Adjust ‘schedule’ documentation
accordingly.
Change-Id: I2a3beb7dffbc9992b714a29423674db9c7dc6cab