The return type of hvt_op_poll() is unsigned int and -EBADF is
inappropriate, poll functions return POLL* statuses.
Reported-by: NDexuan Cui <decui@microsoft.com>
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>