GeoJSON from location/change datatype of location to Geo_Point

Hello, I have incoming data in the below format

    "TestItem": {
        "OriginCountry": "IN",
        "OriginCity": "Banglore",
        "DestinationCountry": "US",
         "DestinationCity":"New York"}

I want to change the datatype to geo_point so that I can view it in Kibana maps, is this poosible via filters in logstash
(I have created region maps in visualization but i am specifically looking to create this in kibana maps)

datatype is defined in ES mapping.