osbuilder: fix missing cpio package when building rootfs-initrd image

1. install cpio package before building rootfs-initrd image
2. add `pipefaili;errexit` check to the scripts

Fixes: #3144

Signed-off-by: Binbin Zhang <binbin36520@gmail.com>

tools/packaging/kata-deploy/local-build/dockerbuild/Dockerfile

@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-FROM ubuntu
+FROM ubuntu:20.04
 ENV DEBIAN_FRONTEND=noninteractive
 ENV INSTALL_IN_GOPATH=false
 
@@ -27,11 +27,12 @@ RUN sh -c "echo '${IMG_USER} ALL=NOPASSWD: ALL' >> /etc/sudoers"
 
 #FIXME: gcc is required as agent is build out of a container build.
 RUN apt-get update && \
-  apt install -y \
-  gcc \
-  git \
-  make \
-  xz-utils
+    apt install --no-install-recommends -y \
+    cpio \
+    gcc \
+    git \
+    make \
+    xz-utils
 
 ENV USER ${IMG_USER}
 USER ${UID}:${GID}