ion: Error out on memory secure failure

All clients have been converted over to the new API
for securing. Instead of silently returning success when
secure fails, error out on a secure failure to allow for proper
error handling.

Change-Id: I57a5c1aef999cfc69a2a9cc1b3e28b2fa74fe3a6
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>