arm64: dts: mediatek: mt6795: Add apmixedsys syscon node

Add the APMIXEDSYS node, providing a syscon to the APMIXED iospace and
also providing PLLs.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230327083647.22017-3-angelogioacchino.delregno@collabora.com
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

Author: AngeloGioacchino Del Regno

arch/arm64/boot/dts/mediatek/mt6795.dtsi

@@ -310,6 +310,12 @@
 			clock-names = "clk13m";
 		};
 
+		apmixedsys: syscon@10209000 {
+			compatible = "mediatek,mt6795-apmixedsys", "syscon";
+			reg = <0 0x10209000 0 0x1000>;
+			#clock-cells = <1>;
+		};
+
 		fhctl: clock-controller@10209f00 {
 			compatible = "mediatek,mt6795-fhctl";
 			reg = <0 0x10209f00 0 0x100>;