Input: ti_am335x_tsc: Mark IRQ as wakeup capable

On AM335x, ti_am335x_tsc can wake up the system from suspend, mark the
IRQ as wakeup capable, so that device irq is not disabled during system
suspend.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>