dt-bindings: arm: Add new compatible for smc/hvc transport for SCMI

Introduce compatible "qcom,scmi-smc" for SCMI smc/hvc transport channel for
Qualcomm virtual platforms.

This compatible mandates populating an additional parameter 'capability-id'
from the last 8 bytes of the shmem channel.

Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Link: https://lore.kernel.org/r/20231009191437.27926-2-quic_nkela@quicinc.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

Documentation/devicetree/bindings/firmware/arm,scmi.yaml

@@ -38,6 +38,9 @@ properties:
                      with shmem address(4KB-page, offset) as parameters
         items:
           - const: arm,scmi-smc-param
+      - description: SCMI compliant firmware with Qualcomm SMC/HVC transport
+        items:
+          - const: qcom,scmi-smc
       - description: SCMI compliant firmware with SCMI Virtio transport.
                      The virtio transport only supports a single device.
         items:
@@ -313,6 +316,7 @@ else:
           enum:
             - arm,scmi-smc
             - arm,scmi-smc-param
+            - qcom,scmi-smc
   then:
     required:
       - arm,smc-id