There's a closed pull request on the void-packages repository

gmic: update to 2.9.9
https://github.com/void-linux/void-packages/pull/33545

Description:
<!-- Mark items with [x] where applicable -->

#### 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)

#### Have the results of the proposed changes been tested?
- [ ] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
- [x] I generally don't use the affected packages but briefly tested this PR

closes #33534

- Successfully built for x86_64, i686, armv7l-musl locally.
- ZArt isn’t included in the gmic source tarball anymore so I added it as a separate distfile. However, there is no release, yet, so I chose to use the latest commit.
- There is a new plugin for krita.
- The problem is that it is a mixed build style (gnu-makefile/qmake).
In a custom `do_build()` function the non-qt and qt targets are now built separately. For some reason it doesn’t seem to work otherwise.
The qt targets get their flags from the qmake build helper (the main `Makefile` calls `qmake`).
However, I had to make a small change to the qmake build helper or else the hardening flags wouldn’t get picked up.
@sgn can you please have a look at it (you committed that part) if you agree? I haven’t tested that change with other packages, though.
- When running `do_install()` gimp’s plug-in-dir is determined via the `gimptool-2.0` command, but it fails in cross builds. So I hardcoded the directory via a sed substitution.
- There are some compiler warnings on 32-bit targets like
```
CImg.h:59420: warning: argument 1 value '4294967295' exceeds maximum object size 2147483647 [-Walloc-size-larger-than=]
```
and
```
../src/CImg.h:6862:15: warning: comparison is always true due to limited range of data type [-Wtype-limits]
 6862 |       return c>=0 && (unsigned char)c<=' ';
```

<!--
If GitHub CI cannot be used to validate the build result (for example, if the
build is likely to take several hours), make sure to
[skip CI](https://github.com/void-linux/void-packages/blob/master/CONTRIBUTING.md#continuous-integration).
When skipping CI, uncomment and fill out the following section.
Note: for builds that are likely to complete in less than 2 hours, it is not
acceptable to skip CI.
-->
<!-- 
#### Does it build and run successfully? 
(Please choose at least one native build and, if supported, at least one cross build. More are better.)
- [ ] I built this PR locally for my native architecture, (ARCH-LIBC)
- [ ] I built this PR locally for these architectures (if supported. mark crossbuilds):
  - [ ] aarch64-musl
  - [ ] armv7l
  - [ ] armv6l-musl
-->


<!--
If GitHub CI cannot be used to validate the build result (for example, if the
build is likely to take several hours), make sure to
[skip CI](https://github.com/void-linux/void-packages/blob/master/CONTRIBUTING.md#continuous-integration).
When skipping CI, uncomment and fill out the following section.
Note: for builds that are likely to complete in less than 2 hours, it is not
acceptable to skip CI.
-->
<!-- 
#### Does it build and run successfully? 
(Please choose at least one native build and, if supported, at least one cross build. More are better.)
- [ ] I built this PR locally for my native architecture, (ARCH-LIBC)
- [ ] I built this PR locally for these architectures (if supported. mark crossbuilds):
  - [ ] aarch64-musl
  - [ ] armv7l
  - [ ] armv6l-musl
-->


<!--
If GitHub CI cannot be used to validate the build result (for example, if the
build is likely to take several hours), make sure to
[skip CI](https://github.com/void-linux/void-packages/blob/master/CONTRIBUTING.md#continuous-integration).
When skipping CI, uncomment and fill out the following section.
Note: for builds that are likely to complete in less than 2 hours, it is not
acceptable to skip CI.
-->
<!-- 
#### Does it build and run successfully? 
(Please choose at least one native build and, if supported, at least one cross build. More are better.)
- [ ] I built this PR locally for my native architecture, (ARCH-LIBC)
- [ ] I built this PR locally for these architectures (if supported. mark crossbuilds):
  - [ ] aarch64-musl
  - [ ] armv7l
  - [ ] armv6l-musl
-->