accel: Fix a leak on Windows HAX

hThread is only used on the error path in hax_kick_vcpu_thread().

Fixes: b0cb0a6 ("Plumb the HAXM-based hardware acceleration support")
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-5-philmd@linaro.org>

target/i386/hax/hax-all.c

@@ -205,6 +205,9 @@ int hax_vcpu_destroy(CPUState *cpu)
      */
     hax_close_fd(vcpu->fd);
     hax_global.vm->vcpus[vcpu->vcpu_id] = NULL;
+#ifdef _WIN32
+    CloseHandle(cpu->hThread);
+#endif
     g_free(vcpu);
     return 0;
 }