boot/optee-os: add option to select DTC dependency

Some platforms (stm32, sam) needs DTC to build the platform
device-trees. Add BR2_TARGET_OPTEE_OS_NEEDS_DTC configuration
option to select host-dtc package when building.

Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Acked-by: Etienne Carriere <etienne.carriere@linaro.org>
[yann.morin.1998@free.fr: move option]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit 67be54cd943a466aab6bf53df2aa9e712da43556)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

boot/optee-os/Config.in

@@ -54,6 +54,13 @@ config BR2_TARGET_OPTEE_OS_VERSION
 	default BR2_TARGET_OPTEE_OS_CUSTOM_REPO_VERSION \
 				if BR2_TARGET_OPTEE_OS_CUSTOM_GIT
 
+config BR2_TARGET_OPTEE_OS_NEEDS_DTC
+	bool "OP-TEE OS needs dtc"
+	select BR2_PACKAGE_HOST_DTC
+	help
+	  Select this option if your OP-TEE OS platform configuration
+	  requires the Device Tree compiler to be available.
+
 config BR2_TARGET_OPTEE_OS_CORE
 	bool "Build core"
 	default y

boot/optee-os/optee-os.mk

@@ -23,6 +23,10 @@ endif
 
 OPTEE_OS_DEPENDENCIES = host-openssl host-python3 host-python-pycryptodomex host-python-pyelftools
 
+ifeq ($(BR2_TARGET_OPTEE_OS_NEEDS_DTC),y)
+OPTEE_OS_DEPENDENCIES += host-dtc
+endif
+
 # On 64bit targets, OP-TEE OS can be built in 32bit mode, or
 # can be built in 64bit mode and support 32bit and 64bit
 # trusted applications. Since buildroot currently references