configs: stm32: Enable DOS_PARTITION for STM32F4/F7 boards

Enable DOS_PARTITION for boards STM32F429-eval, STM32F469-disco
and STM32F746-disco.
This allows to read FAT partition on mmc.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
3 files changed