uboot-phytec

dt-bindings: mtd: stm32_fmc2: add STM32 FMC2 NAND controller documentation

This patch adds the documentation of the device tree bindings for the STM32
FMC2 NAND controller.

Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
Reviewed-by: Patrick DELAUNAY <patrick.delaunay@st.com>