There is an updated pull request by RangHo against master on the void-packages repository

https://github.com/RangHo/void-packages update-libportal
https://github.com/void-linux/void-packages/pull/53691

libportal: update to 0.9.0
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#### Testing the changes
- I tested the changes in this PR: **briefly**

#### Local build testing
- I built this PR locally for my native architecture, `x86_64-glibc`

#### Notes
- This PR is marked as draft because Vala 0.56.16 does not recognize `pid_t` as a valid type[^1]. As such, #53689 must be merged beforehand.

[^1]: https://github.com/GNOME/vala/blob/0732bb119d968a8bab154c308d1498a31aa7d6af/NEWS#L20

A patch file from https://github.com/void-linux/void-packages/pull/53691.patch is attached