ARM: dts: microchip: at91-sama7g5ek: add EEPROMs

The main boot sequence for Microchip AT91 devices is one of the
following:
1/ ROM BOOT -> AT91Bootstrap -> U-Boot -> Linux Kernel
2/ ROM BOOT -> AT91Bootstrap -> Linux Kernel

For case 1/ U-Boot is the stage where the Ethernet MAC addresses are set.
For case 2/ where U-Boot is skipped the Ethernet MAC addresses need to
be configured in Linux. For this add EEPROMs and nvmem-layout to describe
EUI48 MAC address regions.

Signed-off-by: Claudiu Beznea <[e-mail]>
[[e-mail]: Add nvmem-layout to describe eui48 mac
region. Align compatible name with datasheet. Reword commit message.]
Signed-off-by: Andrei Simion <[e-mail]>
[claudiu.beznea: adjusted the new commit message]
Signed-off-by: Claudiu Beznea <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

arch/arm/boot/dts/microchip/at91-sama7g5ek.dts

···
 		i2c-digital-filter;
 		i2c-digital-filter-width-ns = <35>;
 		status = "okay";
+
+		eeprom0: eeprom@52 {
+			compatible = "microchip,24aa025e48";
+			reg = <0x52>;
+			size = <256>;
+			pagesize = <16>;
+			vcc-supply = <&vdd_3v3>;
+
+			nvmem-layout {
+				compatible = "fixed-layout";
+				#address-cells = <1>;
+				#size-cells = <1>;
+
+				eeprom0_eui48: eui48@fa {
+					reg = <0xfa 0x6>;
+				};
+			};
+		};
+
+		eeprom1: eeprom@53 {
+			compatible = "microchip,24aa025e48";
+			reg = <0x53>;
+			size = <256>;
+			pagesize = <16>;
+			vcc-supply = <&vdd_3v3>;
+
+			nvmem-layout {
+				compatible = "fixed-layout";
+				#address-cells = <1>;
+				#size-cells = <1>;
+
+				eeprom1_eui48: eui48@fa {
+					reg = <0xfa 0x6>;
+				};
+			};
+		};
 	};
 };
 
···
 		     &pinctrl_gmac0_txck_default
 		     &pinctrl_gmac0_phy_irq>;
 	phy-mode = "rgmii-id";
+	nvmem-cells = <&eeprom0_eui48>;
+	nvmem-cell-names = "mac-address";
 	status = "okay";
 
 	ethernet-phy@7 {
···
 		     &pinctrl_gmac1_mdio_default
 		     &pinctrl_gmac1_phy_irq>;
 	phy-mode = "rmii";
+	nvmem-cells = <&eeprom1_eui48>;
+	nvmem-cell-names = "mac-address";
 	status = "okay"; /* Conflict with pdmc0. */
 
 	ethernet-phy@0 {