arm64: dts: meson: add dwmac-3.70a to ethmac compatible list

After discussing with Amlogic, the Synopsys GMAC version used by
the gx and axg family is the 3.70a. Set this is in DT
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>

arch/arm64/boot/dts/amlogic/meson-axg.dtsi

@@ -171,7 +171,9 @@ soc {
 		ranges;
 
 		ethmac: ethernet@ff3f0000 {
-			compatible = "amlogic,meson-axg-dwmac", "snps,dwmac";
+			compatible = "amlogic,meson-axg-dwmac",
+				     "snps,dwmac-3.70a",
+				     "snps,dwmac";
 			reg = <0x0 0xff3f0000 0x0 0x10000
 			       0x0 0xff634540 0x0 0x8>;
 			interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;

arch/arm64/boot/dts/amlogic/meson-gx.dtsi

@@ -486,7 +486,9 @@ mailbox: mailbox@404 {
 		};
 
 		ethmac: ethernet@c9410000 {
-			compatible = "amlogic,meson-gx-dwmac", "amlogic,meson-gxbb-dwmac", "snps,dwmac";
+			compatible = "amlogic,meson-gxbb-dwmac",
+				     "snps,dwmac-3.70a",
+				     "snps,dwmac";
 			reg = <0x0 0xc9410000 0x0 0x10000
 			       0x0 0xc8834540 0x0 0x4>;
 			interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;