[llvm] [Offload] Do not link every target for JIT (PR #92013)

[Shilei Tian via llvm-commits]

shiltian wrote:

You could potentially do this in `offload/plugins-nextgen/common/CMakeLists.txt`:

```
foreach(Target ${TargetsSupported})
	target_compile_definitions(PluginCommon PRIVATE "LIBOMPTARGET_JIT_${Target}")
        llvm_map_components_to_libnames(llvm_libs ${Target})
        target_link_libraries(PluginCommon INTERFACE ${llvm_libs})
endforeach()
```

In this way, there is no need for changes of each target. Technically it should have been done on `PluginCommon` since this is the CMake target that needs those symbols.

https://github.com/llvm/llvm-project/pull/92013