Documentation: leds/ledtrig-transient: eliminate duplicated word

Drop the doubled word "for".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: linux-leds@vger.kernel.org
Link: https://lore.kernel.org/r/20200707180414.10467-12-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/leds/ledtrig-transient.rst

@@ -157,7 +157,7 @@ repeat the following step as needed::
 	echo 1 > activate - start timer = duration to run once
 	echo none > trigger
 
-This trigger is intended to be used for for the following example use cases:
+This trigger is intended to be used for the following example use cases:
 
  - Control of vibrate (phones, tablets etc.) hardware by user space app.
  - Use of LED by user space app as activity indicator.