w1: Add 1-Wire uclass

We might want to use 1-Wire devices connected on boards such as EEPROMs in
U-Boot.

Provide a framework to be able to do that.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
[eugen.hristev@microchip.com: reworked]
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
diff --git a/drivers/Makefile b/drivers/Makefile
index 23ea609..4ca07c3 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -105,6 +105,7 @@
 obj-y += soc/
 obj-y += thermal/
 obj-y += axi/
+obj-$(CONFIG_W1) += w1/
 
 obj-$(CONFIG_MACH_PIC32) += ddr/microchip/
 endif