Streaming replication archive folder taking all space- Postgresql- 9.4
Does the archive exist only to support the streaming replication, or do you want it for other reasons like PITR?  (Since you attempted to configure pg_archivecleanup in the first place, I guess I can assume you don't want it for other reasons...)

Because your restore_command is currently broken, then you know that the WAL archive has not been needed thus far to support streaming replication--because if it had been needed it would not have worked.  That is, your replica has never fallen far enough behind that the master has removed the WAL from pg_wal before the replica had fetched it.  If you think that this will always continue to be the case, then you just turn achive_mode = off and delete your current archive.  There is no point in maintaining an archive that is not and cannot be used.

Since the introduction of replication slots, pg_archivecleanup is more-or-less obsolete.  If you want a backstop in case the replica doesn't naturally keep up, you can make a shared mount point and use pg_archivecleanup on that mount point if you want. But configuring a replication slot is a better way to accomplish the same thing.