[ARM] 5259/2: [AT91] PWM LEDs on AT91SAM9263-EK

Use the PWM controller and leds-atmel-pwm.c driver to drive a LED on
the Atmel AT91SAM9263-EK board.

Signed-off-by: Sedji Gaouaou <sedji.gaouaou@atmel.com>
Signed-off-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>