arm64: dts: qcom: ipq5332: add support for the RDP468 variant

Add the initial device tree support for the Reference Design
Platform(RDP) 468 based on IPQ5332 family of SoCs. This patch carries the
support for Console UART, SPI NOR, eMMC.

Signed-off-by: Kathiravan T <quic_kathirav@quicinc.com>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230323093120.20558-3-quic_kathirav@quicinc.com