Remove support for NO_STAGE
Mark all current non staged ports as BROKEN

Reviewed by:	antoine
Exp-run:	antoine
Differential Revision:	https://reviews.freebsd.org/D693


git-svn-id: svn+ssh://svn.freebsd.org/ports/head@366839 35697150-7ecd-e111-bb59-0022644237b5