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To boot on eMMC or SD-cards, STM32MP1 platform needs:
- GPT_IMAGE_ID to read GPT table on those devices
- STM32_IMAGE_ID and IO_TYPE_STM32IMAGE to read images with STM32 header
- IO_TYPE_MMC to have a IO for MMC devices
Signed-off-by: Yann Gautier <yann.gautier@st.com>