I was running some historical tags for the last 10 years and got the
following warnings:

  git log --use-mailmap --numstat --since "June 2010" | ~/src/gitdm.git/gitdm -n -l 5
  alarson@ddci.com is an author name, probably not what you want
  bad utf-8 ('utf-8' codec can't decode byte 0xe4 in position 552: invalid continuation byte) in patchm skipping
  bad utf-8 ('utf-8' codec can't decode byte 0xe4 in position 342: invalid continuation byte) in patchm skipping
  michael@ozlabs.org  is an author name, probably not what you want
  Oops...funky email nicta.com.au
  bad utf-8 ('utf-8' codec can't decode byte 0xe9 in position 232: invalid continuation byte) in patchm skipping
  Oops...funky email andreas.faerber
  Grabbing changesets...done
  Processed 76422 csets from 1902 developers

The following fixes try and alleviate that although I still get a
warning for Aaron which I think is from 9743cd57.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220315121251.2280317-6-alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Acked-by: Aaron Larson <alarson@ddci.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andreas Färber <andreas.faerber@web.de>
Cc: Jason Wang <jasowang@redhat.com>