link the main loop and its dependencies into the tools

Using the main loop code from QEMU enables tools to operate fully
asynchronously.  Advantages include better Windows portability (for some
definition of portability) over glib's.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

oslib-win32.c

@@ -118,3 +118,8 @@ int qemu_gettimeofday(qemu_timeval *tp)
      Do not set errno on error.  */
   return 0;
 }
+
+int qemu_get_thread_id(void)
+{
+    return GetCurrentThreadId();
+}