[LLD] Fix llvm-driver cmake integration for LLD (#76305)

Previously, even though LLD was linked as part of llvm-driver when using
`cmake ... -DLLVM_TOOL_LLVM_DRIVER_BUILD=ON`, there were build issues
when compiling incrementally. Sometimes link errors when linking LLD,
other times, the `llvm.exe` would be impropely be replaced by `lld.exe`.