arm64: dts: stratix10: add board compatible for SoCFPGA DK

The Altera SoCFPGA Stratix 10 SoC Development Kit is a board with
Stratix 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/arm64/boot/dts/altera/socfpga_stratix10_socdk.dts

@@ -7,6 +7,7 @@
 
 / {
 	model = "SoCFPGA Stratix 10 SoCDK";
+	compatible = "altr,socfpga-stratix10-socdk", "altr,socfpga-stratix10";
 
 	aliases {
 		serial0 = &uart0;

arch/arm64/boot/dts/altera/socfpga_stratix10_socdk_nand.dts

@@ -7,6 +7,7 @@
 
 / {
 	model = "SoCFPGA Stratix 10 SoCDK";
+	compatible = "altr,socfpga-stratix10-socdk", "altr,socfpga-stratix10";
 
 	aliases {
 		serial0 = &uart0;