arm64: dts: qcom: sc8280xp: correct SPMI bus address cells

The SPMI bus uses two address cells and zero size cells (second reg
entry - SPMI_USID - is not the size):

  spmi@c440000: #address-cells:0:0: 2 was expected

Fixes: 152d1faf ("arm64: dts: qcom: add SC8280XP platform")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221213101921.47924-3-krzysztof.kozlowski@linaro.org