Refactor Docker scripts

docker/build.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+if [ ! -e docker_conf.inc ]; then
+    echo "This script must be run from within one of the subfolders"
+    exit 1
+fi
+. docker_conf.inc
+# Make sure to connect a Proxmark3 when building if you want to be able to access it from within the Docker instance
+UART_PORT="$(../../pm3 --list|grep /dev|head -n1|cut -d' ' -f2)"
+if [ -n "$UART_PORT" ]; then
+    UART_GID="$(stat -c '%g' $UART_PORT)"
+    BUILDARG="--build-arg UART_GID=$UART_GID"
+else
+    BUILDARG=""
+fi
+
+# For cross-platform support:
+# cf https://github.com/multiarch/qemu-user-static
+#sudo apt install qemu-user-static
+#docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+#docker buildx create --use
+#docker buildx inspect --bootstrap
+#docker buildx build $DOCKER_PLATFORM $BUILDARG -t "$DOCKER_IMAGE" --load .
+# Seems to work without buildx:
+docker build $DOCKER_PLATFORM $BUILDARG -t "$DOCKER_IMAGE" .