board: 8660: Add callbacks to request_region

Callbacks to request_region, release_region,
setup_region is missing from ION platform data for
SMI heap.

Change-Id: Ida603d4ac7c3246c0deedb9b80dc0c1ea64638eb
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
[sboyd: drop board file changes]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>