The changes necessary to build Blender on a Mac with arm64 CPU, using the same steps as build on a x86_64 Mac.
Except for OIDN, this will result in a feature complete but untested and most likely buggy build of Blender.
This is still work in progress - it needs a little bit more cleanup before we can commit this IMHO.
The original patches sent by Apple are archived below and are not necessary or included in this new patch:
These patches were provided by Apple.
Note this patch does not apply on latest master, it is from 5/29/2020.
There is a patch for Blender, and patches for various library dependencies attached below.