Before the line vmbus_open() returns, srv->util_cb can be already running
and the variables, like util_fw_version, are needed by the srv->util_cb.
So we have to make sure the variables are initialized before the vmbus_open().
CC: "K. Y. Srinivasan" <kys@microsoft.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>