get netinet headers from iPhoneSimulator SDK, not iPhoneOS SDK
get netinet headers from iPhoneSimulator SDK, not iPhoneOS SDK

As of SDK 9.2 at least, the headers we need are not part of the device
SDK, only the simulator SDK.

dicej/avian,dicej/avian,dicej/avian,lwahlmeier/avian,MaartenR/avian,MaartenR/avian,MaartenR/avian,lwahlmeier/avian,lwahlmeier/avian,dicej/avian,lwahlmeier/avian,MaartenR/avian