devel: use the new 'config' argument of the develwarn in deprecwarn
Controling all deprecation warnings with the same config seems sensible. This
mirror a fix (about missing gating) submitted for stable but with the new API.
# See http://EditorConfig.org for the specification
root = true
[*.py]
indent_size = 4
indent_style = space
trim_trailing_whitespace = true
[*.{c,h}]
indent_size = 8
indent_style = tab
trim_trailing_whitespace = true