MFC r259266:

MFC r259266:

  Fix multi-repository support by properly respecting 'enabled' flag.

  This will read the REPOS_DIR env/config setting (default is /etc/pkg
  and /usr/local/etc/pkg/repos) and use the last enabled repository.

  This can be changed in the environment using a comma-separated list,
  or in /usr/local/etc/pkg.conf with JSON array syntax of:
      REPOS_DIR: ["/etc/pkg", "/usr/local/etc/pkg/repos"]

Approved by:	bapt (mentor)

git-svn-id: svn://svn.freebsd.org/base/stable/10@259613 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f