dt-bindings: arm: qcom: Document SM8250 SoC and boards

Document the SM8250 SoC binding and also the boards using it.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200904063637.28632-2-manivannan.sadhasivam@linaro.orgSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Documentation/devicetree/bindings/arm/qcom.yaml

@@ -40,6 +40,7 @@ description: |
         sdm630
         sdm660
         sdm845
+        sm8250
 
   The 'board' element must be one of the following strings:
 
@@ -165,4 +166,10 @@ properties:
               - qcom,ipq6018-cp01-c1
           - const: qcom,ipq6018
 
+      - items:
+          - enum:
+              - qcom,qrb5165-rb5
+              - qcom,sm8250-mtp
+          - const: qcom,sm8250
+
 ...