ion: add alignment check to chunk heap

Change-Id: I4be12b9545a81f9b46339a905f00e1e64896b3ed
Signed-off-by: Colin Cross <ccross@android.com>
Git-commit: 1b1cbed2f4cd92b9ccfd28b985983e2d217ecd2e
Git-repo: http://android.googlesource.com/kernel/common/


Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>