New review comment by dkwo on void-packages repository

https://github.com/void-linux/void-packages/pull/32636#discussion_r694148059

Comment:
I'm not sure. The only place I see gtk in meson-options is
`option('docs', type : 'combo', choices : ['none', 'gtkdoc', 'docgen'], value : 'docgen', description : 'developer documentation type')`
so I think they just changed the way they deal with docs.
Do you want to use the value `gtkdoc` instead?
This should explain the comment below.