It doesn't build with newer versions than ffmpeg4, but the the dependency is optional, so we can
drop it if ffmpeg4 is dropped.
No revbump because no rebuild is necessare right now.
Also, remove the version constraints from the lib: requirements. They should be picked up automatically by haikuporter because of the devel: requirements and the dependency of ffmpeg_devel on ffmpeg.
* opencascade: switch to the official version (version 7.7.0)
* completely rewrite the recipe and the patchset
* add all supported libraries and optional dependencies that are available
* tools (command line only) and samples are provided as subpackages
* Tk (and therefore the GUI for DRAW) is not enabled because it hangs on my system
* Xlibe is used to provide a window system
* using both Tk and Xlibe at once is currently not possible due to #7501
* the patchset contains a commit with a stub allowing at least to build without Xlibe, but there is no proper Haiku implementation of it yet. That code path is currently not used.
* EGL is used as OpenGL API, but it doesn't work currently. It displays the following error message:
```
Error: EGL does not provide compatible configurations
```
Test report:
* there are 21000 test cases, so the tests take a while to run
* most tests are skipped due to missing test data (am I missing something how to invoke the tests?)
* the tests involving the Inspector crash into the Debugger because both Xlibe and Qt5 try to create a BApplication when running the Inspector from DRAW (see threedeyes/qthaikuplugins#27)
* some tests hang, pegging one core (although they should have a timeout apparently), they must be aborted manually by killing the secondary DRAWEXE
* the detailed test results are created in $sourceDir/build/results, that folder has 168 MiB zipped
* opencascade: add patch from Liguros to fix finding Qt5 on x86
* opencascade: disable OpenGL, reorganize the patchset a bit
Tools and samples which tried to use OpenGL before will now crash because there is no 3D viewer driver implementation.
x86_64 is used as a baseline: the "x86_64" entry, whatever status it has,
is transformed into "all", and then the other entries in ARCHITECTURES
either dropped or rearranged appropriately.
