GitLab

(vc-sccs-register, vc-sccs-checkin, vc-sccs-find-revision)
(vc-sccs-checkout, vc-sccs-rollback, vc-sccs-revert)
(vc-sccs-steal-lock, vc-sccs-modify-change-comment)
(vc-sccs-print-log): Use it.
* lisp/vc-hooks.el (vc-path): Remove SCCS-specific hack.
* lib-src/vcdiff: Use "sccs get" rather than "get"; leave PATH alone.