[llvm-jitlink] Fix -Wunused-function on Windows

[sgraenitz]

LGTM. Thanks for fixing this!

llvm/tools/llvm-jitlink/llvm-jitlink.cpp

std::unique_ptr<LLVMJITLinkRemoteTargetProcessControl> RTPC(
           std::move(SSP), std::move(Channel), std::move(Endpoint),
           std::move(ReportError), Err));
   if (Err)
     return std::move(Err);
   return std::move(RTPC);
 #endif
 }
 
+#ifdef LLVM_ON_UNIX
 static Error createTCPSocketError(Twine Details) {
   return make_error<StringError>(
       formatv("Failed to connect TCP socket '{0}': {1}",
               OutOfProcessExecutorConnect, Details),
       inconvertibleErrorCode());
 }
 
 static Expected<int> connectTCPSocket(std::string Host, std::string PortStr) {
-#ifndef LLVM_ON_UNIX
-  // FIXME: Add TCP support for Windows.
-  return make_error<StringError>("-" + OutOfProcessExecutorConnect.ArgStr +
-                                     " not supported on non-unix platforms",
-                                 inconvertibleErrorCode());
-#else
   addrinfo *AI;
   addrinfo Hints{};
   Hints.ai_family = AF_INET;
   Hints.ai_socktype = SOCK_STREAM;
   Hints.ai_flags = AI_NUMERICSERV;
 
   if (int EC = getaddrinfo(Host.c_str(), PortStr.c_str(), &Hints, &AI))
     return createTCPSocketError("Address resolution failed (" +
static Expected<int> connectTCPSocket(std::string Host, std::string PortStr) {
   freeaddrinfo(AI);
 
   // If we reached the end of the loop without connecting to a valid endpoint,
   // dump the last error that was logged in socket() or connect().
   if (Server == nullptr)
     return createTCPSocketError(std::strerror(errno));
 
   return SockFD;
-#endif
 }
+#endif
 
 Expected<std::unique_ptr<TargetProcessControl>>
 LLVMJITLinkRemoteTargetProcessControl::ConnectToExecutor() {
 #ifndef LLVM_ON_UNIX
   // FIXME: Add TCP support for Windows.
   return make_error<StringError>("-" + OutOfProcessExecutorConnect.ArgStr +
                                      " not supported on non-unix platforms",
                                  inconvertibleErrorCode());