Add scripts to create build env for other architectures

Dockerfile

@@ -0,0 +1,10 @@
+ARG DOCKER_ARCH
+FROM ${DOCKER_ARCH}debian:bullseye as build_env
+
+# Default packages
+RUN apt-get -y update && apt-get -y install gnupg2 libavformat-dev libavutil-dev libavcodec-dev v4l-utils pkg-config xxd build-essential ccache
+
+# Add RPI packages
+RUN echo "deb http://archive.raspberrypi.org/debian/ bullseye main" > /etc/apt/sources.list.d/raspi.list
+RUN apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 82B129927FA3303E
+RUN apt-get -y update && apt-get -y install libcamera-dev liblivemedia-dev