[oe] make explosion while building attr

[Cliff Brake]

On Sat, May 8, 2010 at 2:28 PM, Cliff Brake <cliff.brake at gmail.com> wrote:
> It would be really nice to be able to rename TOPDIR in bitbake to
> something like BB_TOPDIR, so we don't run into this problem.  Perhaps
> it is not necessary to whitelist TOPDIR to get BB to use it -- guess I
> need to try that as well.

It looks like the TOPDIR env variable does not need to be white-listed
in order for BB to use it, so that is the correct solution.

Cliff