ARM: dts: aspeed: ast2600-evb-a1: Add compatible

The AST2600 EVB A1 is an AST2600 EVB.
Signed-off-by: Joel Stanley <joel@jms.id.au>

arch/arm/boot/dts/aspeed-ast2600-evb-a1.dts

@@ -5,7 +5,7 @@
 
 / {
 	model = "AST2600 A1 EVB";
-	compatible = "aspeed,ast2600-evb-a1", "aspeed,ast2600";
+	compatible = "aspeed,ast2600-evb-a1", "aspeed,ast2600-evb", "aspeed,ast2600";
 
 	/delete-node/regulator-vcc-sdhci0;
 	/delete-node/regulator-vcc-sdhci1;