w1: add command for onewire protocol

Add basic command for bus information and read for onewire
bus using Dallas 1-Wire protocol.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
diff --git a/cmd/Kconfig b/cmd/Kconfig
index cf97a0f..1e4ab6e 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -832,6 +832,13 @@
 	help
 	  I2C support.
 
+config CMD_W1
+	depends on W1
+	default y if W1
+	bool "w1 - Support for Dallas 1-Wire protocol"
+	help
+	  Dallas 1-wire protocol support
+
 config CMD_LOADB
 	bool "loadb"
 	default y