arm64: dts: meson-sm1-odroid-hc4: add spifc node to ODROID-HC4

Add a node for the XT25F128B SPI-NOR flash to make it accessible
from Linux.

Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20210607065435.577334-7-narmstrong@baylibre.com