Update the libc_test.

- Refactored the fencepost testing code, include adding a fencepost
  before the buffer (when not using the value returned by malloc).
- Add a verbose option to display more information as the test runs.
- Change the test to stop on the first fail rather than keep going.

Change-Id: I24614293563689ad0f59d6aadd21d717cd080684
1 file changed