There is a new pull request by kawaiiamber against master on the void-packages repository

https://github.com/kawaiiamber/void-packages gstreamer
https://github.com/void-linux/void-packages/pull/28657

gstreamer1: add missing makedepends
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#### General
- [ ] This is a new package and it conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements)

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I noticed when building the `gstreamer1` package with `xbps-src` that it warns about missing libraries:
![1612995217](https://user-images.githubusercontent.com/30329373/107582857-52f66a00-6bb7-11eb-884a-1cd5c5c497c3.png)
![1612995198](https://user-images.githubusercontent.com/30329373/107582864-54279700-6bb7-11eb-86ac-230a905bd63c.png)

Furthermore, I notice that the [PKGBUILD](https://github.com/archlinux/svntogit-packages/blob/packages/gstreamer/trunk/PKGBUILD) on Arch includes these libraries in their template. This might help with [this](https://github.com/void-linux/void-packages/issues/25852) issue. I notice that durring the build is says that pkg-config can't find gstreamer-1.0.pc in `PKG_CONFIG_PATH`. I used `xlocate gstreamer-1.0.pc` and tried adding, as a result:
```sh
export PKG_CONFIG_PATH="${PKG_CONFIG_PATH}:${DESTDIR}/usr/lib/pkgconfig"
```
as that is the directory where `gstreamer-1.0.pc` is located, but the same warning occurs.

A patch file from https://github.com/void-linux/void-packages/pull/28657.patch is attached