Add bootstrap and build files

Author: facchinm

extra/bootstrap.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+if [ ! -f platform.txt ]; then
+  echo Launch this script from the root core folder as ./extras/bootstrap.sh
+  exit 2
+fi
+
+python3 -m venv venv
+source venv/bin/activate
+pip install west
+west init -l .
+west update
+# download slim toolchain from https://github.com/zephyrproject-rtos/sdk-ng/releases/tag/v0.16.8

extra/build.sh

@@ -0,0 +1,16 @@
+export ZEPHYR_SDK_INSTALL_DIR=/ssd/zephyr-sdk-0.16.8/
+
+set -e
+
+board=$1
+variant=$2
+
+if [[ $# -eq 0 ]]; then
+board=arduino_giga_r1//m7
+variant=arduino_giga_r1_m7
+fi
+
+(west build loader -b $board -p && west build -t llext-edk)
+(tar xvfp build/zephyr/llext-edk.tar.xz --directory variants/$variant/)
+(cp build/zephyr/zephyr.elf firmwares/zephyr-$variant.elf)
+(cp build/zephyr/zephyr.bin firmwares/zephyr-$variant.bin)