Bug#1043048: openblas: gives wrong results on mips64el, ignores test failures

[Rebecca N. Palmer]

>> The most obviously relevant
>> change between those is that the installed BLAS changed from atlas to
>> openblas.

It looks like this wasn't a change of default, but that experimental 
uses libatlas and unstable uses libopenblas.

(I don't know why, as the obvious dependency chain is src:statsmodels -> 
python3-scipy -> python3-pythran -> libopenblas-dev | libatlas-base-dev 
on both, and libopenblas is installable in experimental.)

> It looks like version 0.3.21+ds-4 is not affected by this issue and
> passes its testsuite. Can you possibly check whether statsmodels builds
> against that version?

It did (successfully) in statsmodels version 0.13.5+dfsg-7.  The 
openblas build logs also show the issue starting between .21 and .22.