ARM: dts: msm: add SPMI PMIC arbiter device for lito

Add SPMI PMIC arbiter device so that it is possible to
communicate with PMICs attached to the SPMI bus.

Change-Id: I6d62c3e45e107fab82c96988b04387353beaa4a7
Signed-off-by: Umang Agrawal <uagrawal@codeaurora.org>