[acpica] Avoid undefined behavior

Upstream:
- https://github.com/acpica/acpica/pull/852.
- https://github.com/acpica/acpica/pull/853.
- https://github.com/acpica/acpica/pull/854.

Bug: 41663
Change-Id: I8654d84892a5a4576acfd70bb5104052d4c08baa
3 files changed
tree: b94f19b5a8c4da99b2df126c1a4591a74a06d4be
  1. include/
  2. source/
  3. BUILD.gn
  4. changes.txt
  5. LICENSE
  6. OWNERS
  7. README.fuchsia