arm64: dts: qcom: sc7180: Add SPMI PMIC arbiter device

Add SPMI PMIC arbiter device to communicate with PMICs
attached to SPMI bus.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20191108092824.9773-10-rnayak@codeaurora.org


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>