repo : transfer to ggml-org

[ggerganov]

At the right time, when the project is in a healthy state and has enough maintenance support, we will transfer it to the ggml-org Github organization. See the roadmap for the pending things that need to happen before that. The most important requirement for this transfer to occur is to have an active maintainer(s) for the whisper.cpp project, ideally someone who is or will become part of ggml-org.