local-build: install s390-tools in Dockerfile

This is to install s390-tools including genprotimg during the docker
build.

Signed-off-by: Hyounggyu Choi <Hyounggyu.Choi@ibm.com>

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

@@ -48,6 +48,7 @@ RUN apt-get update && \
   gcc \
   unzip \
   xz-utils && \
+  if uname -m | grep -Eq 's390x'; then apt-get install -y s390-tools; fi && \
   apt-get clean && rm -rf /var/lib/apt/lists
 
 ENV USER ${IMG_USER}