Fix docker build with debian bullseye image

- Fix missing sfdisk which is not included anymore in bullseye container
- Fix problem with binfmt_misc not being mounted inside docker although present on host

Dockerfile

@@ -8,7 +8,7 @@ RUN apt-get -y update && \
         git vim parted \
         quilt coreutils qemu-user-static debootstrap zerofree zip dosfstools \
         libarchive-tools libcap2-bin rsync grep udev xz-utils curl xxd file kmod bc\
-        binfmt-support ca-certificates qemu-utils kpartx \
+        binfmt-support ca-certificates qemu-utils kpartx fdisk \
     && rm -rf /var/lib/apt/lists/*
 
 COPY . /pi-gen/

build-docker.sh

@@ -98,6 +98,8 @@ if [ "${CONTAINER_EXISTS}" != "" ]; then
 		--volumes-from="${CONTAINER_NAME}" --name "${CONTAINER_NAME}_cont" \
 		pi-gen \
 		bash -e -o pipefail -c "dpkg-reconfigure qemu-user-static &&
+	# binfmt_misc is sometimes not mounted with debian bullseye image
+	(mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc || true) &&
 	cd /pi-gen; ./build.sh ${BUILD_OPTS} &&
 	rsync -av work/*/build.log deploy/" &
 	wait "$!"
@@ -112,6 +114,8 @@ else
 		-e "GIT_HASH=${GIT_HASH}" \
 		pi-gen \
 		bash -e -o pipefail -c "dpkg-reconfigure qemu-user-static &&
+	# binfmt_misc is sometimes not mounted with debian bullseye image
+	(mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc || true) &&
 	cd /pi-gen; ./build.sh ${BUILD_OPTS} &&
 	rsync -av work/*/build.log deploy/" &
 	wait "$!"