[scudo] Fix static and unused function type annotations am: f389921570 am: 75edaff9b6

Original change: https://android-review.googlesource.com/c/platform/external/scudo/+/2045292

Change-Id: Ie3d0660cc55de7ae3e5e067ca5188aa7ab6fd375
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>