hwmon: (bt1-pvt) Wait for the completion with timeout

hwmon: (bt1-pvt) Wait for the completion with timeout

[ Upstream commit 0ffd21d5985506d164ada9e8fff6daae8ef469a1 ]

If the PVT sensor is suddenly powered down while a caller is waiting for
the conversion completion, the request won't be finished and the task will
hang up on this procedure until the power is back up again. Let's call the
wait_for_completion_timeout() method instead to prevent that. The cached
timeout is exactly what we need to predict for how long conversion could
normally last.

Fixes: 87976ce2825d ("hwmon: Add Baikal-T1 PVT sensor driver")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920110924.19741-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>