Fix build from missing label in fab78f3b7d14194658a5af81de0e42728861cf32
ports -l: Support -n like jail does.

Requested by:	jhb
Fix cleaning_pool run hook (bad env definition)
Merge branch 'master' into dragonfly

Conflicts:
	src/bin/poudriere.8
	src/share/poudriere/ports.sh