dm: led: add BCM6328 led driver

This driver is a simplified version of linux/drivers/leds/leds-bcm6328.c,
simplified to remove HW leds and blink fallbacks.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/led/Makefile b/drivers/led/Makefile
index 02367fd..d371ed5 100644
--- a/drivers/led/Makefile
+++ b/drivers/led/Makefile
@@ -6,4 +6,5 @@
 #
 
 obj-y += led-uclass.o
+obj-$(CONFIG_LED_BCM6328) += led_bcm6328.o
 obj-$(CONFIG_$(SPL_)LED_GPIO) += led_gpio.o