[llvm] [Offload] libomptarget force dlopen vendor libraries by default. (PR #92788)

[Ye Luo via llvm-commits]

ye-luo wrote:

> Does #87009 really make a difference? I thought that in the old case we would simply `dlopen` on the old `libomptarget.rtl.cuda.so` that would then be linked against `libcuda.so` directly.

In the old case, dlopen `libomptarget.rtl.cuda.so` fails but the user programs continue.

https://github.com/llvm/llvm-project/pull/92788