mpc85xx: drop WS-AP3715i label-mac

Label MAC detection does not work properly, as MAC address is assigned
on preinit. Thus, remove the label-mac definition.

Signed-off-by: David Bauer <[email protected]>

target/linux/mpc85xx/files/arch/powerpc/boot/dts/ws-ap3715i.dts

@@ -13,7 +13,6 @@
 		led-failsafe = &led_power_red;
 		led-running = &led_power_green;
 		led-upgrade = &led_power_red;
-		label-mac-device = &enet0;
 	};
 
 	chosen {