Add hotdoc "--fatal-warnings" option

GStreamer uses the --fatal-warnings hotdoc option to check for completeness of docs modification. There’s currently no (documented at least) way to pass this option to hotdoc when integrated into meson.

Ideally, the module itself would implement this option.

Cc @MathieuDuponchelle

[xclaesse]

I recently added infrastructure in Meson to have per-module options, would make sense to use that to support -Dhotdoc.fatal_warnings=true option.

[MathieuDuponchelle]

I recently added infrastructure in Meson to have per-module options, would make sense to use that to support -Dhotdoc.fatal_warnings=true option.

That’s great, I remember the python module could also use a module-level option btw, in order to pick the python version instead of requiring the option be exposed in each project (slightly off-topic I know)