ARM: dts: aspeed: Modify I2C bus configuration

Enable I2C bus 8 which is exposed on the IPMB_1 connector on the X570D4U
mainboard.

Additionally adds a descriptive comment to I2C busses 1 and 5.
Signed-off-by: Renze Nicolai <renze@rnplus.nl>
Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>

arch/arm/boot/dts/aspeed/aspeed-bmc-asrock-x570d4u.dts

@@ -162,6 +162,7 @@ &i2c0 {
 };
 
 &i2c1 {
+	/* Hardware monitoring SMBus */
 	status = "okay";
 
 	w83773g@4c {
@@ -219,6 +220,7 @@ i2c4mux0ch3: i2c@3 {
 };
 
 &i2c5 {
+	/* SMBus on BMC connector (BMC_SMB_1) */
 	status = "okay";
 };
 
@@ -243,6 +245,11 @@ eth1_macaddress: macaddress@3f88 {
 	};
 };
 
+&i2c8 {
+	/* SMBus on intelligent platform management bus header (IPMB_1) */
+	status = "okay";
+};
+
 &gfx {
 	status = "okay";
 };