arm64: dts: qcom: sm8450: Add SDHCI2

Add and configure the SDHCI host responsible for (mostly) SD Card and
its corresponding pins' sleep states.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220714123406.1919836-4-konrad.dybcio@somainline.org