internal/socket: remove leftover AF_* and SOCK_RAW constants on aix
internal/socket: remove leftover AF_* and SOCK_RAW constants on aix

Follow-up for CL 53310 which changed internal/socket to use these
constants from golang.org/x/sys/unix

Change-Id: I40fde84c875995fbeef2d21f8e05f5ba27b11098
Reviewed-on: https://go-review.googlesource.com/c/net/+/178557
Run-TryBot: Tobias Klauser <0a68dd4915066ec5d3f81f75a828fee53dcc8822@gmail.com>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

golang/net