If a GSI stop channel command leaves the channel in STOP_IN_PROC
state, we retry the stop command after a 1-2 millisecond delay.

I have been told that a 3-5 millisecond delay is a better choice.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>