dt-bindings: power: qcom-rpmpd: Add MSM8909 power domains

MSM8909 has the same power domains as MSM8916 so just define them
as aliases for the existing definitions.

Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220705143523.3390944-4-stephan.gerhold@kernkonzept.com