stm32mp: stm32prog: add flash layout parsing

Build the list of device and of partition with
a tab separated value file with a stm32 header: the FlashLayout.tsv
(https://wiki.st.com/stm32mpu/wiki/STM32CubeProgrammer_flashlayout

)

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