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>