ramips-mt7621: fix xiaomi mi ac2100 mac address

The Xiaomi Redmi/Mi Router AC2100 does have the correct label mac on the WAN interface.
This MAC is available as gmac1.

Signed-off-by: Florian Maurer <f.maurer@outlook.de>
Link: openwrt/openwrt#22567
(cherry picked from commit b1713d6)
Link: openwrt/openwrt#22624
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

Author: maurerle

target/linux/ramips/dts/mt7621_xiaomi_mi-router-ac2100.dts

@@ -13,7 +13,7 @@
 		led-failsafe = &led_status_yellow;
 		led-running = &led_status_blue;
 		led-upgrade = &led_status_blue;
-		label-mac-device = &gmac0;
+		label-mac-device = &gmac1;
 	};
 
 	leds {

target/linux/ramips/dts/mt7621_xiaomi_redmi-router-ac2100.dts

@@ -13,7 +13,7 @@
 		led-failsafe = &led_status_amber;
 		led-running = &led_status_white;
 		led-upgrade = &led_status_white;
-		label-mac-device = &gmac0;
+		label-mac-device = &gmac1;
 	};
 
 	leds {