[ARM] 5267/1: [AT91] Name conflict in mach-at91/leds.c

The name of the platform device 'at91_pwm_leds' conflicts with the
function at91_pwm_leds().
So rename the device 'at91_pwm_leds_device' to be more specific.
Similarly rename 'at91_gpio_leds_device' for consistency.

Signed-off-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>