dt-bindings: power: rpmpd: Add sc7280 to rpmpd binding

Add compatible and constants for the power domains exposed by the RPMH
in the Qualcomm Technologies Inc sc7280 platform.

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Link: https://lore.kernel.org/r/1614664092-9394-1-git-send-email-rnayak@codeaurora.org


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