ARM: dts: arria10: add board compatible for SoCFPGA DK

The Altera SoCFPGA Arria 10 SoC Development Kit is a board with Arria 10,
so it needs its own compatible.
Signed-off-by: NKrzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: NDinh Nguyen <dinguyen@kernel.org>

arch/arm/boot/dts/socfpga_arria10_socdk.dtsi

@@ -6,7 +6,7 @@
 
 / {
 	model = "Altera SOCFPGA Arria 10";
-	compatible = "altr,socfpga-arria10", "altr,socfpga";
+	compatible = "altr,socfpga-arria10-socdk", "altr,socfpga-arria10", "altr,socfpga";
 
 	aliases {
 		ethernet0 = &gmac0;