Include g++ binaries to build C++ python dependencies

Author: jbatonnet

build/1-buildroot/gcc-target.patch

@@ -105,7 +105,7 @@ index 00000000..4fc6d9b9
 +	--disable-lto
 +# Finally, we add some of our own flags
 +GCC_TARGET_CONF_OPTS += \
-+	--enable-languages=c \
++	--enable-languages=c,c++ \
 +	--disable-boostrap \
 +	--disable-libgomp \
 +	--disable-nls \

build/3-python/install-packages.sh

@@ -6,6 +6,7 @@ mkdir -p $PIP_TEMP
 
 export PATH=/usr/libexec/gcc/arm-buildroot-linux-uclibcgnueabihf/11.4.0:$PATH
 export CC=/usr/bin/gcc
+export CXX=/usr/bin/g++
 export LD_LIBRARY_PATH=/lib:/usr/lib
 export HOME=$PIP_TEMP
 export TMPDIR=$PIP_TEMP