libumpalumpa/operations/initialization/cuda.cpp not implemented properly

Branch: master

When running tests, cuda and starpu versions crash with 
```
[Info] Initializing tuner for device NVIDIA GeForce RTX 2060 with Max-Q Design
unknown file: Failure
C++ exception with description "vector::_M_range_check: __n (which is 0) >= this->size() (which is 0)" thrown in the test body.
```

Also, it can only set values to `0` now, which is limiting