Add neon lib support

[yanghuan95]

HI, I see there is wslay lib in devkitPro, it's support for websocket.
Would neno lib add also? I see this can pretty handle webdav, and with this, we can easy access NAS or other cloud disk.
Thanks.

Also, I want to no, why mmap can't be used? It's helpfull to reduce file copy between user and kernel. When I send/recive file in network, I can improve the file transalte rate.

[yanghuan95]

Actually, this need in switch, thanks