linux-phytec-fsl

MLK-13632 driver: watchdog: Fix system reset when sending wdog unlock sequence

For i.MX7ULP wdog, when we want to unlock the wdog with 16bit unlock command,
the two unlock command sequence must be write to WDOG_CNT register within 16 bus
clocks, otherwise, system may be reset unexpected. As writel include memory barrier,
if we use writel to send the unlock command, it may take more time than 16 bus clock,
so we should use writel_relaxed to write the unlock command to the CNT register.

Signed-off-by: Bai Ping <ping.bai@nxp.com>