sysutils/s6: Upgrade to version 2.14.0.1.

Changes from NEWS file:

• Bugfixes.
• Support for shared libraries on MacOS.
• New -m option to s6-accessrules-cdb-from-fs.
• New Rperiod directive for s6-log periodic rotations.
• s6-svc now accepts several service directory arguments.
• s6-svc now exits 102 on unsupervised directory argument.
• New s6-background-watch binary, to counter auto-backgrounding.
• s6-fghack is now obsolescent.
• New -P prio option to s6-softlimit.