configmgr: Delete unused struct volume_control
configmgr: Delete unused struct volume_control

Change-Id: Iddf18279cb599447db4bbf4967914396082ccb02
Signed-off-by: Richard Fitzgerald <22ee0097135072451429b5ac45630d52779cd49b@opensource.cirrus.com>

CirrusLogic/tinyhal,CirrusLogic/tinyhal,CirrusLogic/tinyhal