gpu: ion: Add msm specific extensions to CMA heap

A number of changes have been made to the Ion framework for the
msm target. Add the necessary changes on top of the CMA heap to
allow the CMA heap to be fully utilized.

Change-Id: Ie006dcd4c41481e4d914c67bafbf42d1afdb1a76
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>