Add build flow control script

build_w_flow_ctrl.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+BASE_DIR="$(dirname ${BASH_SOURCE[0]})"
+BUILD_DIR=$BASE_DIR/build
+PICO_SDK_DIR=$BASE_DIR/pico-sdk
+
+main() {
+	if [ ! -d "$PICO_SDK_DIR/.git" ]; then
+		git submodule sync --recursive
+		git submodule update --init --recursive
+	fi
+
+	cmake -DFLOW_CONTROL=true -B $BUILD_DIR -S $BASE_DIR
+	make -C $BUILD_DIR
+}
+
+main $@