Workaround for GHC bug #5797 for Windows platform

There is a known bug in GHC for Windows that prevents some socket calls (at least recv and accept) from being interrupted by async exception. Please see https://ghc.haskell.org/trac/ghc/ticket/5797 for additional info.

This bug creates difficulties when using network-conduit with Control.Concurrent.Async.Lifted functions (since threads are no longer interrupted by cancel). I can confirm that this patch fixes this problem for Windows.