ACPI: EC: add newline when printing 'ec_event_clearing' module parameter

When I cat acpi module parameter
'/sys/module/acpi/parameters/ec_event_clearing', it displays as follows.
It is better to add a newline for easy reading.

[root@hulk-202 ~]# cat /sys/module/acpi/parameters/ec_event_clearing
query[root@hulk-202 ~]#

Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>