Upstream RV change broke compilation
See https://zivgitlab.uni-muenster.de/HPC2SE-Project/pacxx-rv2/-/jobs/13665
The error is:
```
/builds/HPC2SE-Project/pacxx-rv2/llvm/projects/pacxxrt/lib/native/transforms/SPMDVectorizer.cpp: In member function 'virtual bool {anonymous}::SPMDVectorizer::runOnModule(llvm::Module&)':
/builds/HPC2SE-Project/pacxx-rv2/llvm/projects/pacxxrt/lib/native/transforms/SPMDVectorizer.cpp:191:12: error: 'struct rv::Config' has no member named 'useSLEEF'
config.useSLEEF = true;
^
/builds/HPC2SE-Project/pacxx-rv2/llvm/projects/pacxxrt/lib/native/transforms/SPMDVectorizer.cpp:198:50: error: too many arguments to function 'void rv::addSleefResolver(const rv::Config&, rv::PlatformInfo&)'
rv::addSleefResolver(config, platformInfo, 35);
^
In file included from /builds/HPC2SE-Project/pacxx-rv2/llvm/projects/pacxxrt/lib/native/transforms/SPMDVectorizer.cpp:39:0:
/builds/HPC2SE-Project/pacxx-rv2/llvm/projects/pacxxrt/../../tools/rv/include/rv/resolver/resolvers.h:12:8: note: declared here
void addSleefResolver(const Config & config, PlatformInfo & platInfo);
^
make[2]: *** [projects/pacxxrt/CMakeFiles/PACXXTransforms.dir/lib/native/transforms/SPMDVectorizer.cpp.o] Error 1
```
- Upstream [556a59a8f5b1cdfc442a5de60d12d76028492927](https://github.com/cdl-saarland/rv/commit/556a59a8f5b1cdfc442a5de60d12d76028492927): Last working upstream commit appearing in a [CI run](https://gitlab.dune-project.org/joe/pacxx-docker/-/jobs/61006).
- Upstream [44f2a4c48eb5ffa127c74e51daef6cfe0c66e71e](https://github.com/cdl-saarland/rv/commit/44f2a4c48eb5ffa127c74e51daef6cfe0c66e71e): Probably working.
- Upstream [255b27fa06e4046f73ae2cc50c009737f0ccd7ef](https://github.com/cdl-saarland/rv/commit/255b27fa06e4046f73ae2cc50c009737f0ccd7ef): probable culprit.
- Upstream [e3431eca756ead153556576ccbae2a913729413f](https://github.com/cdl-saarland/rv/commit/e3431eca756ead153556576ccbae2a913729413f): Definitely broken, see the CI job up top.
TODO:
- [x] Pin rv2 master to a working upstream commit (!13)
- [x] Make an rv2 branch/MR to follow upstream master again (!14)
- [x] Make a matching runtime branch/MR to fix the build failures (pacxx-runtime!43)
issue