This lets us include the package on those platforms in a
followup commit where we split out a conn package from device.
It also lets us run `go test ./...` when developing on macOS.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
On my Chromebook (Linux 4.19.44 in a VM) and on an AWS EC2
machine, select() was sometimes returning EINTR. This is
harmless and just means you should try again. So let's try
again.
This eliminates a problem where the tunnel fails to come up
correctly and the program needs to be restarted.
Signed-off-by: Avery Pennarun <apenwarr@gmail.com>
