tree-wide: fix typos "couter" -> "counter"

This patch was generated by

	git grep -E -i -l 'couter' | xargs -r perl -p -i -e 's/couter/counter/'

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

kernel/irq/spurious.c

@@ -230,7 +230,7 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
 		/*
 		 * If we are seeing only the odd spurious IRQ caused by
 		 * bus asynchronicity then don't eventually trigger an error,
-		 * otherwise the couter becomes a doomsday timer for otherwise
+		 * otherwise the counter becomes a doomsday timer for otherwise
 		 * working systems
 		 */
 		if (time_after(jiffies, desc->last_unhandled + HZ/10))