dt-bindings: firmware: arm,scmi: Allow multiple instances

dt-bindings: firmware: arm,scmi: Allow multiple instances

Enable multiple SCMI instances by appending an instance-number suffix
to the 'scmi' node name. The SCMI spec assumes a single SCMI platform,
but in practice its responsibilities may be split across several SCMI
platform/server instances. However, only one instance can serve as the
system-wide (true) SCMI platform.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com>
Signed-off-by: Deepti Jaggi <quic_djaggi@quicinc.com>
Message-Id: <20250730-8255-scmi-v6-1-a7d8ba19aded@quicinc.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>