staging: IIO corrected the spelling in iio-trig-gpio

Corrected the spelling.
Signed-off-by: Nanish kumar <anish198519851985@gmail.com>
Acked-by: NJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/trigger/iio-trig-gpio.c

@@ -7,7 +7,7 @@
  * under the terms of the GNU General Public License version 2 as published by
  * the Free Software Foundation.
  *
- * Currently this is more of a functioning proof of concept that a fully
+ * Currently this is more of a functioning proof of concept than a full
  * fledged trigger driver.
  *
  * TODO: