powerpc: dts: t208x: Disable 10G on MAC1 and MAC2

There aren't enough resources to run these ports at 10G speeds. Disable
10G for these ports, reverting to the previous speed.

Fixes: 36926a7d ("powerpc: dts: t208x: Mark MAC1 and MAC2 as 10G")
Reported-by: Camelia Alexandra Groza <camelia.groza@nxp.com>
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Camelia Groza <camelia.groza@nxp.com>
Tested-by: Camelia Groza <camelia.groza@nxp.com>
Link: https://lore.kernel.org/r/20221216172937.2960054-1-sean.anderson@seco.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

arch/powerpc/boot/dts/fsl/t2081si-post.dtsi

@@ -659,3 +659,19 @@ L2_1: l2-cache-controller@c20000 {
 		interrupts = <16 2 1 9>;
 	};
 };
+
+&fman0_rx_0x08 {
+	/delete-property/ fsl,fman-10g-port;
+};
+
+&fman0_tx_0x28 {
+	/delete-property/ fsl,fman-10g-port;
+};
+
+&fman0_rx_0x09 {
+	/delete-property/ fsl,fman-10g-port;
+};
+
+&fman0_tx_0x29 {
+	/delete-property/ fsl,fman-10g-port;
+};