arm64: dts: qcom: sm8250: Define CPU topology

sm8250 has a big.LITTLE CPU setup with DynamIQ, so all cores are within
the same CPU cluster and LLC (Last-Level Cache) domain. Define this
topology to help the scheduler make decisions.

Signed-off-by: Danny Lin <danny@kdrag0n.dev>
Link: https://lore.kernel.org/r/20210112013255.415253-1-danny@kdrag0n.dev


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