Atomics.wake(...) always returns 0 on non-win32 platforms

[rwaldron]

While working on Atomics tests for Test262, I observed that any test which checked that the return value of Atomics.wake(...) was some non-zero value, the test would fail. I've tracked the cause:

https://github.com/Microsoft/ChakraCore/blob/c0723f4985c468937c6ac12260bdbe5da6d25539/lib/Runtime/Library/SharedArrayBuffer.cpp#L764-L780

[fatcerberus]

On a related tangent, TC39 has apparently agreed to rename Atomics.wake to Atomics.notify. See, e.g. this Node.js issue:
nodejs/node#21219