Input: egalax-ts - fix typo and improve text

Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/egalax-ts.txt

@@ -6,7 +6,7 @@ Required properties:
 - interrupt-parent: the phandle for the interrupt controller
 - interrupts: touch controller interrupt
 - wakeup-gpios: the gpio pin to be used for waking up the controller
-  as well as uased as irq pin
+  and also used as irq pin
 
 Example: