powerpc: dts: t1040rdb: enable both CPU ports

Since commit eca70102 ("net: dsa: felix: add support for changing
DSA master") included in kernel v6.1, the driver supports 2 CPU ports,
and they can be put in a LAG, for example (see
Documentation/networking/dsa/configuration.rst for more details).

Defining the second CPU port in the device tree should not cause any
compatibility issue, because the default CPU port was &seville_port8
before this change, and still is &seville_port8 now (the numerically
first CPU port is used by default).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

arch/powerpc/boot/dts/fsl/t1040rdb.dts

@@ -180,6 +180,9 @@ &seville_port7 {
 };
 
 &seville_port8 {
-	ethernet = <&enet0>;
+	status = "okay";
+};
+
+&seville_port9 {
 	status = "okay";
 };

arch/powerpc/boot/dts/fsl/t1040si-post.dtsi

@@ -686,6 +686,7 @@ seville_port7: port@7 {
 			seville_port8: port@8 {
 				reg = <8>;
 				phy-mode = "internal";
+				ethernet = <&enet0>;
 				status = "disabled";
 
 				fixed-link {
@@ -697,6 +698,7 @@ fixed-link {
 			seville_port9: port@9 {
 				reg = <9>;
 				phy-mode = "internal";
+				ethernet = <&enet1>;
 				status = "disabled";
 
 				fixed-link {