Cycles: add Point Info node

With (center) position, radius and random value outputs.

Eevee does not yet support rendering point clouds, but an untested
implementation of this node was added for when it does.

Ref T92573

release/scripts/startup/nodeitems_builtins.py

@@ -390,6 +390,7 @@ shader_node_categories = [
         NodeItem("ShaderNodeAmbientOcclusion"),
         NodeItem("ShaderNodeObjectInfo"),
         NodeItem("ShaderNodeHairInfo"),
+        NodeItem("ShaderNodePointInfo"),
         NodeItem("ShaderNodeVolumeInfo"),
         NodeItem("ShaderNodeParticleInfo"),
         NodeItem("ShaderNodeCameraData"),