Add
commit 90205f67e4
Author: Segher Boessenkool <segher@kernel.crashing.org>
Date: Mon Oct 25 23:29:26 2021 +0000
rs6000: Fix bootstrap (libffi)
This fixes bootstrap for the current problems building libffi.
to LOCAL_PATCHES.
* LOCAL_PATCHES: Add commit 90454a9008.