watchdog: starfive: Fix the probe return error if PM and early_enable are both disabled

When the starfive watchdog driver uses 'pm_runtime_put_sync()' as probe
return value at last and 'early_enable' is disabled, it could return the
error '-ENOSYS' if the CONFIG_PM is disabled, but the driver should works
normally.

Drop the 'return' and keep the 'pm_runtime_put_sync()', but do not use it
as the return value.

Fixes: db728ea9 ("drivers: watchdog: Add StarFive Watchdog driver")
Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230426031216.37981-1-xingyu.wu@starfivetech.com


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