ARM: dts: BCM53573: Fix Tenda AC9 switch CPU port

Primary Ethernet interface is connected to the port 8 (not 5).

Fixes: 6461282 ("ARM: dts: BCM53573: Add Tenda AC9 switch ports")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Link: https://lore.kernel.org/r/20230723195416.7831-1-zajec5@gmail.com
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>

Author: Rafał Miłecki

arch/arm/boot/dts/broadcom/bcm47189-tenda-ac9.dts

@@ -135,8 +135,8 @@
 			label = "lan4";
 		};
 
-		port@5 {
-			reg = <5>;
+		port@8 {
+			reg = <8>;
 			label = "cpu";
 			ethernet = <&gmac0>;
 		};