board: dh_stm32mp1: remove env location override

Overriding the environment location is not necessary as the defconfig
for the relevant boards only enable SPI flash and nowhere sources which
are in the same order per default but having this explicit override
prevents using eMMC or SD card (or EXT4) as environment source.

Signed-off-by: Jakob Riepler <jakob.riepler@aviloo.com>
Reviewed-by: Patrick Delaunay <patrick.delaunay@st.com>
1 file changed