stm32mp: add binman support for STM32MP15x

Use binman to add the stm32image header on SPL binary for basic boot
or on U-Boot binary when it is required, i.e. for TF-A boot without FIP
support, when CONFIG_STM32MP15x_STM32IMAGE is activated.

The "binman" tool is the recommended tool for specific image generation.
This patch allows to suppress the config.mk file and it is a preliminary
step to manage FIT generation with binman.

The init_r parsing of U-Boot device tree to search the binman
information is not required for STM32MP15, so the binman library
can be removed in U-Boot (CONFIG_BINMAN_FDT is deactivated).

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-stm32mp/Kconfig b/arch/arm/mach-stm32mp/Kconfig
index 69d56c2..4acb293 100644
--- a/arch/arm/mach-stm32mp/Kconfig
+++ b/arch/arm/mach-stm32mp/Kconfig
@@ -37,6 +37,7 @@
 	bool "Support STMicroelectronics STM32MP15x Soc"
 	select ARCH_SUPPORT_PSCI if !TFABOOT
 	select ARM_SMCCC if TFABOOT
+	select BINMAN
 	select CPU_V7A
 	select CPU_V7_HAS_NONSEC if !TFABOOT
 	select CPU_V7_HAS_VIRT