ARM: dts: qcom: sdx65: Add SCM node

Add SCM node to enable SCM functionality on SDX65 platform.

Signed-off-by: Rohit Agarwal <quic_rohiagar@quicinc.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1654080312-5408-6-git-send-email-quic_rohiagar@quicinc.com