Ensure overlay files are owned by root.

This may not be correct in all use cases but for the files that are currently created,
they should be owned by root.  At a minimum they should not have the UID of the user
invoking mender-convert.

Changelog: Title
Signed-off-by: Drew Moseley <drew.moseley@northern.tech>

scripts/bootstrap-rootfs-overlay-demo-server.sh

@@ -74,4 +74,6 @@ ${server_ip} docker.mender.io s3.docker.mender.io
 EOF
 wget -q "https://raw.githubusercontent.com/mendersoftware/mender/master/support/demo.crt" -O ${output_dir}/etc/mender/server.crt
 
+sudo chown -R root.root ${output_dir}
+
 echo "Configuration file for using Demo Mender Server written to: ${output_dir}/etc/mender"

scripts/bootstrap-rootfs-overlay-hosted-server.sh

@@ -64,4 +64,6 @@ cat <<- EOF > ${output_dir}/etc/mender/mender.conf
 }
 EOF
 
+sudo chown -R root.root ${output_dir}
+
 echo "Configuration file for using Hosted Mender written to: ${output_dir}/etc/mender"

scripts/bootstrap-rootfs-overlay-production-server.sh

@@ -77,4 +77,6 @@ cat <<- EOF >> ${output_dir}/etc/mender/mender.conf
 }
 EOF
 
+sudo chown -R root.root ${output_dir}
+
 echo "Configuration file for using Production Mender Server written to: ${output_dir}/etc/mender"