NetBSD doesn't provide neither SO_PEERCRED nor LOCAL_PEERCRED
but wayland 1.24.0 would like to get the socket peer credentials,
leading to

../src/wayland-os.c:129:2: error: #error "Don't know how to read ucred on this platform"
  129 | #error "Don't know how to read ucred on this platform"
      |  ^~~~~

