I would assume one of them is a symbolic link, but you are right. It seems both are shipped and should be identical, if I’m not mistaken:
ll libtorch/lib
[...]
185727360 Mar 23 21:02 libdnnl.a
185727360 Mar 23 21:02 libmkldnn.a
[...]

Could you create an issue on GitHub and link to this thread, please?