Avoid unused parameter warnings for unsupported platforms
Avoid unused parameter warnings for unsupported platforms

Summary: Wangle's `initWithSocket` and `readRTT` functions result in unused parameter warnings (often treated as an error) when they are used in an unsupported platform. This diff silences the warnings to prevent wangle compilation failures.

Reviewed By: yfeldblum

Differential Revision: D23617510

fbshipit-source-id: 1a042b745309681cff00ff4c46236a0d8e072bd3

facebook/wangle,facebook/wangle,facebook/wangle