app_queue.c: Extract some functions for simpler code.

* Extract set_queue_member_pause() from set_member_paused() for simpler
and more consistent code.

* Extract set_queue_member_ringinuse() from
set_member_ringinuse_help_members() for simpler code.

Change-Id: Iecc1f4119c63347341d7ea6b65f5fc4963706306