Wait for the socket thread to finish when unloading, close the open socket.

The Android loader dlopens a layer twice, so if the layer did not clean up
properly the first time it is unloaded then we will fail to open a socket
on the default port 38920 during the second dlopen.

renderdoc/core/core.cpp

@@ -320,6 +320,7 @@ RenderDoc::~RenderDoc()
   {
     m_RemoteServerThreadShutdown = true;
     // don't join, just close the thread, as we can't wait while in the middle of module unloading
+    Threading::Sleep(50);
     Threading::CloseThread(m_RemoteThread);
     m_RemoteThread = 0;
   }

renderdoc/core/remote_access.cpp

@@ -353,6 +353,8 @@ void RenderDoc::RemoteAccessServerThread(void *s)
   Threading::CloseThread(clientThread);
   clientThread = 0;
 
+  SAFE_DELETE(sock);
+
   Threading::ReleaseModuleExitThread();
 }