stm32mp1: configs: add spi load support in spl

Add the boot for NOR, SPL load U-Boot.img at offset
CONFIG_SYS_SPI_U_BOOT_OFFS = 0x80000.
It is the start address of mtd partition ssbl in nor.

Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
diff --git a/arch/arm/mach-stm32mp/Kconfig b/arch/arm/mach-stm32mp/Kconfig
index 187be17..c9bc084 100644
--- a/arch/arm/mach-stm32mp/Kconfig
+++ b/arch/arm/mach-stm32mp/Kconfig
@@ -16,6 +16,7 @@
 	select SPL_REGMAP
 	select SPL_DM_RESET
 	select SPL_SERIAL_SUPPORT
+	select SPL_SPI_LOAD
 	select SPL_SYSCON
 	select SPL_WATCHDOG_SUPPORT if WATCHDOG
 	imply BOOTSTAGE_STASH if SPL_BOOTSTAGE