Apple Silicon support

Tracking issue for Apple Silicon (ARM64) support of GDK:

• Brew installation ✅
• Brew-based GDK dependencies ❌
  • Go (git-lfs dep among others) 1.15 fails to compile: https://github.com/golang/go/issues/38485
  • Guile (gpg dep) 3.0.4 fails: Log
  • google-chrome install crashes in /usr/local/Homebrew/Library/Homebrew/cask/utils/quarantine.swift
• Ruby 2.6.6 ✅
  • Brew based installation works
  • RVM fails on libffi: https://github.com/rvm/rvm/issues/4968, https://github.com/libffi/libffi/issues/571
• GDK make install fails because asdf does not support arm64, in install pre-requisites
  • Arch 'arm64' not supported!