stm32mp1: Add support for raw NAND boot device

STM32MP1 platform is able to boot from raw NAND devices.
These modifications add this support using the new
raw NAND framework.

Change-Id: I9e9c2b03930f98a5ac23f2b6b41945bef43e5043
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
diff --git a/plat/st/stm32mp1/include/boot_api.h b/plat/st/stm32mp1/include/boot_api.h
index c80aef6..ba5d22f 100644
--- a/plat/st/stm32mp1/include/boot_api.h
+++ b/plat/st/stm32mp1/include/boot_api.h
@@ -33,6 +33,9 @@
 /* Boot occurred on EMMC */
 #define BOOT_API_CTX_BOOT_INTERFACE_SEL_FLASH_EMMC		0x2U
 
+/* Boot occurred on FMC */
+#define BOOT_API_CTX_BOOT_INTERFACE_SEL_FLASH_NAND_FMC		0x3U
+
 /**
  * @brief  Possible value of boot context field 'EmmcXferStatus'
  */