Fix brk/sbrk error checking. am: f36b5088a3 am: 1d358c8ed4  -s ours am: f3a1f4244d am: c0c1abe518
am: b6789dc3b5

* commit 'b6789dc3b5fbf8bbd6b407ffe53668138e828655':
  Fix brk/sbrk error checking.

Change-Id: Ief90c1e5bac313ff5a2d18117e70b67e62ced301