gpu: ion: Add support for device tree.

Add device tree parsing to common msm ion code
to allow new targets to specify ION heap configuration
in device tree.

Document the device tree bindings for ION.

Change-Id: I40b7f4b1fbb3ca4ad1d6dc06a33b647f6af1d669
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
4 files changed