board: stm32mp1: use FDT address provided by TF-A at boot time

Save and use the FDT address provided by TF-A in r2 at boot time
(it is NT_FW_CONFIG = Non Trusted Firmware configuration file)

Address is saved in save_boot_params(), called by start.S
and the used DTB is gd->fdt_blob = board_fdt_blob_setup().

If dtb is not provided or invalid, U-Boot use as fallback
the builtin DTB.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
diff --git a/arch/arm/mach-stm32mp/Makefile b/arch/arm/mach-stm32mp/Makefile
index eee39c2..2b8631d 100644
--- a/arch/arm/mach-stm32mp/Makefile
+++ b/arch/arm/mach-stm32mp/Makefile
@@ -13,6 +13,7 @@
 obj-y += bsec.o
 obj-$(CONFIG_CMD_STM32KEY) += cmd_stm32key.o
 obj-$(CONFIG_ARMV7_PSCI) += psci.o
+obj-$(CONFIG_TFABOOT) += boot_params.o
 endif
 
 obj-$(CONFIG_$(SPL_)DM_REGULATOR) += pwr_regulator.o