ARM: dts: stm32: Use DT alias for the configuration EEPROM

Use DT /aliases node to establish a stable phandle to the configuration
EEPROM. This permits the configuration EEPROM to be moved e.g. to a
different address or a different bus. Adjust the board code to handle
new phandle lookup.
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>
Reviewed-by: NPatrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: Patrice Chotard <patrice.chotard@st.com>

arch/arm/dts/stm32mp15xx-dhcom.dtsi

@@ -10,6 +10,10 @@
 #include <dt-bindings/mfd/st,stpmic1.h>
 
 / {
+	aliases {
+		eeprom0 = &eeprom0;
+	};
+
 	memory@c0000000 {
 		device_type = "memory";
 		reg = <0xC0000000 0x40000000>;
@@ -187,7 +191,7 @@
 		};
 	};
 
-	eeprom@50 {
+	eeprom0: eeprom@50 {
 		compatible = "atmel,24c02";
 		reg = <0x50>;
 		pagesize = <16>;

board/dhelectronics/dh_stm32mp1/board.c

@@ -78,22 +78,21 @@ DECLARE_GLOBAL_DATA_PTR;
 
 int setup_mac_address(void)
 {
-	struct udevice *dev;
-	ofnode eeprom;
 	unsigned char enetaddr[6];
-	int ret;
+	struct udevice *dev;
+	int off, ret;
 
 	ret = eth_env_get_enetaddr("ethaddr", enetaddr);
 	if (ret)	/* ethaddr is already set */
 		return 0;
 
-	eeprom = ofnode_path("/soc/i2c@5c002000/eeprom@50");
-	if (!ofnode_valid(eeprom)) {
-		printf("Invalid hardware path to EEPROM!\n");
-		return -ENODEV;
+	off = fdt_path_offset(gd->fdt_blob, "eeprom0");
+	if (off < 0) {
+		printf("%s: No eeprom0 path offset\n", __func__);
+		return off;
 	}
 
-	ret = uclass_get_device_by_ofnode(UCLASS_I2C_EEPROM, eeprom, &dev);
+	ret = uclass_get_device_by_of_offset(UCLASS_I2C_EEPROM, off, &dev);
 	if (ret) {
 		printf("Cannot find EEPROM!\n");
 		return ret;