Provide a simple way to obtain the native GPIO driver used by the controller

This is related to this issue: https://github.com/dotnet/iot/issues/1467

@joperezr [suggested to use reflection](https://github.com/dotnet/iot/issues/1467#issuecomment-791040524) to obtain the driver type name

I am proposing to add a new member that returns the driver name so that it is easier to make diagnostic.
Over the time we have seen many issues that could be solved simply by changing the driver. Adding a property with the driver `System.Type` is simple and could greatly help diagnostics.

I am wondering whether we could also expose the native driver name as well (`libgpiod` / `sysfs`).

There is an additional thing to consider. Certain peripherals can be created without specifying the controller (null as parameter). The controller is then created under the hood but it is not accessible from the code. In this case there would not be the possibility to obtain the driver name.

I would add the detected _board model_ as well.