input: Typo fix in atkbd.c comment

From: Christian Ludwig <cl81@gmx.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>

drivers/input/keyboard/atkbd.c

@@ -771,7 +771,7 @@ static void atkbd_set_device_attrs(struct atkbd *atkbd)
 }
 
 /*
- * atkbd_connect() is called when the serio module finds and interface
+ * atkbd_connect() is called when the serio module finds an interface
  * that isn't handled yet by an appropriate device driver. We check if
  * there is an AT keyboard out there and if yes, we register ourselves
  * to the input module.