Discovering the cuda libraries with dynamic loading

[LaurentMazare]

Hello, First thanks for all the great work on this crate, we rely heavily on it in candle and it has worked very well. We recently updated candle to the 0.11 release including the dynamic loading change in #197 and some users got into some issues with locating libcuda.so , e.g. here https://github.com/huggingface/candle/issues/2175 I've just tweaked candle to be back at dynamic linking rather than dynamic loading as a quick fix but I'm wondering how dynamic loading is supposed to work if the cuda libraries are not in the user LD_LIBRARY_PATH (or in a system lib dir). When using dynamic linking, the RUNPATH is set appropriately in the binary so that the shared libraries will be found when the binary is launched, however in the loading case I'm not sure if there is an equivalent.