ion: Fail system secure heap creation if system heap is unavailable

The system secure heap relies on the existence of the system
heap. Thus, if the system heap is not available, do not create,
the system secure heap.

Change-Id: I7a99e0fda45ae02ed6e5c8a797d29e917e84f182
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>