arm64: dts: r8a7795: salvator-x: Update memory node to 4 GiB map

This patch addes memory region:

  - After changes, the Salvator-X board has the following map:
    Bank0: 1GiB RAM : 0x000048000000 -> 0x0007fffffff
    Bank1: 1GiB RAM : 0x000500000000 -> 0x0053fffffff
    Bank2: 1GiB RAM : 0x000600000000 -> 0x0063fffffff
    Bank3: 1GiB RAM : 0x000700000000 -> 0x0073fffffff

  - Before changes, the old map looked like this:
    Bank0: 1GiB RAM : 0x000048000000 -> 0x0007fffffff
Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts

@@ -56,6 +56,21 @@ memory@48000000 {
 		reg = <0x0 0x48000000 0x0 0x38000000>;
 	};
 
+	memory@500000000 {
+		device_type = "memory";
+		reg = <0x5 0x00000000 0x0 0x40000000>;
+	};
+
+	memory@600000000 {
+		device_type = "memory";
+		reg = <0x6 0x00000000 0x0 0x40000000>;
+	};
+
+	memory@700000000 {
+		device_type = "memory";
+		reg = <0x7 0x00000000 0x0 0x40000000>;
+	};
+
 	x12_clk: x12 {
 		compatible = "fixed-clock";
 		#clock-cells = <0>;