IOMX: do not clear buffer if it's allocated by component am: ea76573aa2 am: 86d9bb9141 am: dfe5b5193c am: b308b1a5d9 am: 87415a74ee
am: 130eb563b8

Change-Id: I8a6ee92a0077102d93f6c9e82b5f439f99e4749c