MNL_SOCKET_BUFFER_SIZE is not defined on macOS since libmnl.h is for Linux only but  0.0.20171001 still attempts to use it, leading to build failure

A full build log is here: https://gist.github.com/ilovezfs/ae19ee8af5b64bc1e89b453b2283b53f

The error is "ipc.c:891:45: error: use of undeclared identifier 'MNL_SOCKET_BUFFER_SIZE'"

Ref: https://github.com/Homebrew/homebrew-core/pull/18822