mips: dts: ralink: mt7621: rename watchdog node from 'wdt' into 'watchdog'

Watchdog nodes must use 'watchdog' for node name. When a 'make dtbs_check'
is performed the following warning appears:

wdt@100: $nodename:0: 'wdt@100' does not match '^watchdog(@.*|-[0-9a-f])?$'

Fix this warning up properly renaming the node into 'watchdog'.

Reviewed-by: Arınç ÜNAL <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Signed-off-by: Sergio Paracuellos <[email protected]>
Acked-by: Guenter Roeck <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

Author: paraka

arch/mips/boot/dts/ralink/mt7621.dtsi

@@ -70,7 +70,7 @@
 					     "250m", "270m";
 		};
 
-		wdt: wdt@100 {
+		wdt: watchdog@100 {
 			compatible = "mediatek,mt7621-wdt";
 			reg = <0x100 0x100>;
 		};