docker: add packages expected by buildroot

Signed-off-by: Olof Johansson <olof@lixom.net>

docker/Dockerfile

@@ -7,7 +7,11 @@ RUN set -e; \
 	apt-get -y upgrade; \
 	:
 
-RUN apt-get -y install wget make tar p7zip-full squashfs-tools vim e2fsprogs parted dosfstools acpica-tools mtools device-tree-compiler xz-utils sudo gcc libssl-dev python2 bison flex u-boot-tools git bc fuseext2 e2tools multistrap qemu-user-static
+RUN apt-get -y install wget make tar p7zip-full squashfs-tools vim \
+	e2fsprogs parted dosfstools acpica-tools mtools \
+	device-tree-compiler xz-utils sudo gcc libssl-dev python2 \
+	bison flex u-boot-tools git bc fuseext2 e2tools multistrap \
+	qemu-user-static g++ cpio python unzip rsync
 
 # build environment
 WORKDIR /work