clocksource/drivers/owl: pr_err() strings should end with newlines

pr_err() messages should end with a new-line to avoid other messages being
concatenated.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>