optee: add timeout value to optee_notif_wait() to support timeout

Add timeout value to support self waking when timeout to avoid waiting
indefinitely.

Signed-off-by: Gavin Liu <gavin.liu@mediatek.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>