This patch updates the documentation for arguments regarding the `Gizmo`
type.
- Corrected `select_id` doc for draw_preset_ functions. `-1` indicates
that no selection ID is to be written, but previous docs incorrectly
specified `0` instead.
- Added missing doc for `target` argument for `target_set_handler`
function.
Reviewed by: Aaron Carlisle (Blendify)
Differential Revision: https://developer.blender.org/D14834
ccdf189d3c