BF(TST): use = (native) instead of < (little endian) for target data types
 - [ ] closes #14830
 - [ ] tests added / passed
 - [ ] passes ``git diff upstream/master | flake8 --diff``
 - [ ] whatsnew entry

It is still WiP -- just thought to submit a PR to see how travis etc reacts on typical platforms
thanks @yarikoptic  Please CP this fix into your 0.19.x branch 0.19.x is closed :(
0.20.0 up next