Add CHD-zstd support

[rtissera]

Changes proposed in this pull request:

• Adds support for zstd / cdzs compression in CHD format
• Adjust CMake packaging
• Fix buffer overflow detected in gdb when using --cdimage option

@midwan

[rtissera]

The CI / Docker images need to be adjusted to bundle zstd

[midwan]

Thank you!
I'll need to adjust the docker images and the pipelines to test the automated builds. The wiki also needs an update of course.

[rtissera]

Amazing @midwan I will replicate on https://github.com/blitterStudio/amiberry-lite/ once ready here

[rtissera]

Thanks for updating your CI stuff.
Removed some lingering debug code, let's see your CI goes on.

[midwan]

Looks like find_package doesn't work for zstd in some environments, while it works on others.
Fedora and older Debian distros specifically.
The Apple builds should work, I tested them manually. They fail in the PR, because the Apple Certificate the CI is trying to use, is not available on your repo (which is expected).

[rtissera]

@midwan I looked at CI logs and okay, understood for Apple builds.
How do we fix the CMake find_package on older distros ?

[midwan]

I've added a review comment about that, I think it will work (at least, it did on Fedora) if you change the Dependencies file a bit.

[rtissera]

@midwan can't locate your comment, but yes, we need a fallback for older CMake actually wich do not bundle FindZstd

[midwan]

Maybe my comments weren't visible, how about now?

[rtissera]

it's good, debug stuff was already removed, let me try the find_helper

[rtissera]

@midwan looks good now no ?

[midwan]

Merged, thanks!

[rtissera]

perfect, let me replicate on https://github.com/blitterStudio/amiberry-lite/