Revert "ARM: dts: msm: Disable ATOS for apps smmu for sm8150"

This reverts commit 17933a7c.
Since the software workaround for the ATOS bug is implemented,
we can now re-enable ATOS.

Change-Id: Id004c61eb0e5e0a6d9c62073a86f273951e40ef9
Signed-off-by: Sudarshan Rajagopalan <sudaraja@codeaurora.org>