[Buildroot] package/dotnet: add host-dotnet-sdk

[Andrey Nechypurenko]

Hi,

> Regarding Andrey's patch, I'm not sure if that is the correct approach, I
> mean, the idea is okay for most of the cases, but what if you install the
> dotnet-runtime -> v5.0.0 and the package that you want to install needs
> v3.1.0 ?

AFAIK, it is possible to have multiple runtimes installed. There are many
ways to say which one should be used by a particular application. One of
them, for example, using DOTNET_ENVIRONMENT environment variable (
https://docs.microsoft.com/en-us/aspnet/core/fundamentals/environments?view=aspnetcore-5.0
) . Also, AFAIK, if the application is packaged with runtime, it will use
this packaged version even if there is separate runtime installed.

Anyway, I think there is no "right way" [tm]. It depends on the application.
For example, in a well controlled environment such as an embedded system
where only a predefined set of applications is installed, common runtime
would be preferable because it saves a considerable amount of space if
multiple applications need it.

Regards,
Andrey.