ARM: dts: msm: Add proxy client node for ATOLL

Proxy bus client is required to ensure that a certain
minimum state for a critical resource at the beginning
of boot up before the clients have probed and voted for
required state. Also introduce a governor that keeps
SNOC/CNOC alive with a very small vote while CPU is active.

Change-Id: Ia1b4469684292301664ca2914b1699bcebcaaa6f
Signed-off-by: Odelu Kukatla <okukatla@codeaurora.org>