firmware: qcom_scm: Add MDM9607 compatible

Add a compatible for MDM9607. It uses the "legacy" calling
convention.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Link: https://lore.kernel.org/r/20210131013058.54299-1-konrad.dybcio@somainline.org


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