dt-bindings: timestamp: Add Tegra264 support

Add timestamp provider support for the Tegra264 in devicetree
bindings. Tegra264 has two generic timestamping engines (GTE)
which are the always-on GTE (AON) and legacy interrupt
controller (LIC) GTE.
'nvidia,slices' property is deprecated and hence not allowed for
Tegra264.

Signed-off-by: Suneel Garapati <suneelg@nvidia.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Dipen Patel <dipenp@nvidia.com>

Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml

@@ -25,6 +25,8 @@ properties:
       - nvidia,tegra194-gte-lic
       - nvidia,tegra234-gte-aon
       - nvidia,tegra234-gte-lic
+      - nvidia,tegra264-gte-aon
+      - nvidia,tegra264-gte-lic
 
   reg:
     maxItems: 1
@@ -112,10 +114,22 @@ allOf:
           contains:
             enum:
               - nvidia,tegra234-gte-aon
+              - nvidia,tegra264-gte-aon
     then:
       required:
         - nvidia,gpio-controller
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - nvidia,tegra264-gte-aon
+              - nvidia,tegra264-gte-lic
+    then:
+      properties:
+        nvidia,slices: false
+
 additionalProperties: false
 
 examples: