[PATCH v3 0/5] OpenBSD & AIX etc. portability fixes

This grew a bit more. I'm going to stop poking at this for now. The tests are still broken on OpenBSD (3-5 broken) and on AIX something like 20-30 are broken, but this makes it slightly better.

Ævar Arnfjörð Bjarmason (5):
  tests: fix and add lint for non-portable head -c N
  tests: fix and add lint for non-portable seq
  tests: use shorter here-docs in chainlint.sed for AIX sed
  tests: fix version-specific portability issue in Perl JSON
  tests: fix and add lint for non-portable grep --file

 t/chainlint.sed                      |  8 ++++----
 t/check-non-portable-shell.pl        |  3 +++
 t/t0019/parse_json.perl              |  3 +++
 t/t5310-pack-bitmaps.sh              |  2 +-
 t/t5318-commit-graph.sh              |  2 +-
 t/t5552-skipping-fetch-negotiator.sh | 12 ++++++------
 t/t5703-upload-pack-ref-in-want.sh   |  4 ++--
 t/test-lib.sh                        |  4 ++--
 8 files changed, 22 insertions(+), 16 deletions(-)