leds: Standardise LED naming scheme

As discussed on LKML some notion of 'function' is needed in
LED naming. This patch adds this to the documentation and
standardises existing LED drivers.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
diff --git a/arch/arm/mach-ixp4xx/dsmg600-setup.c b/arch/arm/mach-ixp4xx/dsmg600-setup.c
index 6886596..8cb0743 100644
--- a/arch/arm/mach-ixp4xx/dsmg600-setup.c
+++ b/arch/arm/mach-ixp4xx/dsmg600-setup.c
@@ -71,11 +71,11 @@
 
 static struct gpio_led dsmg600_led_pins[] = {
 	{
-		.name		= "power",
+		.name		= "dsmg600:green:power",
 		.gpio		= DSMG600_LED_PWR_GPIO,
 	},
 	{
-		.name		= "wlan",
+		.name		= "dsmg600:green:wlan",
 		.gpio		= DSMG600_LED_WLAN_GPIO,
 		.active_low	= true,
 	},