arm64: dts: allwinner: a100: Add syscon nodes

The Allwinner A100 has a system configuration block, denoted as SYS_CFG
in the user manual's memory map. It is undocumented in the manual, but
a glance at the vendor tree shows this block is similar to its
predecessors in the A64 and H6. The A100 also has 3 SRAM blocks: A1, A2,
and C. Add all of these to the SoC's device tree.

Reviewed-by: Parthiban Nallathambi <parthiban@linumiz.com>
Signed-off-by: Cody Eksal <masterr3c0rd@epochal.quest>
Link: https://patch.msgid.link/20241218-a100-syscon-v2-2-dae60b9ce192@epochal.quest
Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Author: BrokenR3C0RD

arch/arm64/boot/dts/allwinner/sun50i-a100.dtsi

@@ -101,6 +101,39 @@
 		#size-cells = <1>;
 		ranges = <0 0 0 0x3fffffff>;
 
+		syscon: syscon@3000000 {
+			compatible = "allwinner,sun50i-a100-system-control",
+				     "allwinner,sun50i-a64-system-control";
+			reg = <0x03000000 0x1000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges;
+
+			sram_a1: sram@20000 {
+				compatible = "mmio-sram";
+				reg = <0x00020000 0x4000>;
+				#address-cells = <1>;
+				#size-cells = <1>;
+				ranges = <0 0x00020000 0x4000>;
+			};
+
+			sram_c: sram@24000 {
+				compatible = "mmio-sram";
+				reg = <0x024000 0x21000>;
+				#address-cells = <1>;
+				#size-cells = <1>;
+				ranges = <0 0x024000 0x21000>;
+			};
+
+			sram_a2: sram@100000 {
+				compatible = "mmio-sram";
+				reg = <0x0100000 0x14000>;
+				#address-cells = <1>;
+				#size-cells = <1>;
+				ranges = <0 0x0100000 0x14000>;
+			};
+		};
+
 		ccu: clock@3001000 {
 			compatible = "allwinner,sun50i-a100-ccu";
 			reg = <0x03001000 0x1000>;