boot/uboot: add BR2_TARGET_UBOOT_USE_BINMAN option

Recent version of U-Boot use binman to provide a mechanism for building
images, from simple SPL + U-Boot combinations, to more complex
arrangements with many parts.

This tool uses additional host python modules that must be provided by
Buildroot. So introduce a new option BR2_TARGET_UBOOT_USE_BINMAN to
add additional host packages in U-Boot build dependency to use binman.

The binman requirement is directly included in buildman dependency
(tools/buildman/requirements.txt) since within U-Boot, binman is
invoked by the build system, here buildman [1].

[1] https://docs.u-boot.org/en/v2024.01/develop/package/binman.html#invoking-binman-within-u-boot

Co-developed-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>

boot/uboot/Config.in

@@ -295,6 +295,17 @@ config BR2_TARGET_UBOOT_NEEDS_ROCKCHIP_RKBIN
 	  This option makes sure that the needed binary blobs are copied
 	  into the U-Boot source directory.
 
+config BR2_TARGET_UBOOT_USE_BINMAN
+	bool "U-Boot use binman"
+	depends on BR2_PACKAGE_HOST_RUSTC_TARGET_ARCH_SUPPORTS # python-rpds-py -> python-jsonschema
+	select BR2_TARGET_UBOOT_NEEDS_PYTHON3
+	select BR2_TARGET_UBOOT_NEEDS_PYELFTOOLS
+	select BR2_TARGET_UBOOT_NEEDS_PYLIBFDT
+	help
+	  Use binman tool for generation and signing of boot images.
+
+	  https://docs.u-boot.org/en/v2024.01/develop/package/binman.html
+
 menu "U-Boot binary format"
 
 config BR2_TARGET_UBOOT_FORMAT_AIS

boot/uboot/uboot.mk

@@ -279,6 +279,14 @@ ifeq ($(BR2_TARGET_UBOOT_NEEDS_XXD),y)
 UBOOT_DEPENDENCIES += host-vim
 endif
 
+ifeq ($(BR2_TARGET_UBOOT_USE_BINMAN),y)
+# https://source.denx.de/u-boot/u-boot/-/blob/v2024.01/tools/buildman/requirements.txt
+UBOOT_DEPENDENCIES += \
+	host-python-jsonschema \
+	host-python-pyyaml
+UBOOT_MAKE_OPTS += BINMAN_INDIRS=$(BINARIES_DIR)
+endif
+
 # prior to u-boot 2013.10 the license info was in COPYING. Copy it so
 # legal-info finds it
 define UBOOT_COPY_OLD_LICENSE_FILE