libavb: Allow AvbOps functions to fail with OOM.

To do this we have to slightly change some public library API so we can
bubble up OOM failures. Also fix up the boot_control implementation
since it's using some of this API.

Also fix two warnings found by compiling with gcc instead of clang.

Bug: None
Change-Id: I241ee10e10cef5d7f7ec8db418b279a2a2543c9e
Test: All unit tests pass.
8 files changed
tree: 7ec2e4a5d7693b6d6b87f2f926adb3038d565b03
  1. boot_control/
  2. libavb/
  3. test/
  4. Android.mk
  5. avbtool
  6. LICENSE
  7. README