Introduce Soong target libmemoffset_nostd am: 46edeb14c3 am: 03a37ce18a

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/memoffset/+/2952669

Change-Id: I6edaf6118f480460acedf907e6d18c10b332778e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>