stm32mp1: board: add support of CONFIG_ENV_IS_IN_MMC

Add support of CONFIG_ENV_IS_IN_MMC in env_get_location, used for
all mmc device (SD card and eMMC).
The 2 configs CONFIG_ENV_IS_IN_MMC and CONFIG_ENV_IS_IN_EXT4 are
incompatible.

Add the weak function mmc_get_env_dev to select the mmc boot instance.

Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
1 file changed