Implements a simple splash screen notice displayed if an x86/Intel macOS Blender build is ran on an Apple Silicon Mac to warn against reduced performance. On the technical side of things, this adds a function that detects if the current process is currently running through Rosetta using `sysctl`. Implementation wise, I tried to keep this function contained in a single conditional preprocessor macro block in the same file for simplicity. Co-authored-by: Harley Acheson <harley.acheson@gmail.com> Pull Request: https://projects.blender.org/blender/blender/pulls/124382