watchdog: rti-wdt: Add missing pm_runtime_disable() in probe function

If the probe fails, we should use pm_runtime_disable() to balance
pm_runtime_enable().

Fixes: 2d63908b

 ("watchdog: Add K3 RTI watchdog support")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220105092114.23932-1-linmq006@gmail.com


Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>