arm64: dts: rockchip: add (but disabled) SFC node for Radxa ROCK 5A

This commit adds SFC node for Radxa ROCK 5A.

since sdhci and sfc on RK3588s share pins(i.e. exclusive), it cannot
be enabled both nodes at the same time. so status = "okay" is omitted
here.

you may be able to enable sfc (and disable sdhci) by fdt overlay.

SPI NOR flash chip may vary, so use safe(lowest) spi-max-frequency.
Signed-off-by: FUKAUMI Naoki <naoki@radxa.com>
Link: https://lore.kernel.org/r/20240623023329.1044-2-naoki@radxa.comSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3588s-rock-5a.dts

@@ -376,6 +376,19 @@ &sdmmc {
 	status = "okay";
 };
 
+&sfc {
+	pinctrl-names = "default";
+	pinctrl-0 = <&fspim0_pins>;
+
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+		spi-max-frequency = <104000000>;
+		spi-rx-bus-width = <4>;
+		spi-tx-bus-width = <1>;
+	};
+};
+
 &spi2 {
 	status = "okay";
 	assigned-clocks = <&cru CLK_SPI2>;