deploy: ISO rebuild: use -joliet-long names.

deploy: ISO rebuild: use -joliet-long names.

Armband adds similar files, which tend to have long names and only
differ in suffixes (e.g. DEBs for amd64 vs arm64).

Previous change [1] fixed ISO build errors, but failed to address
the deploy.py ISO rebuild (which modifies and recreates the ISO,
calling mkisofs, which complains about clashing file indexes).

This works around ISO rebuild error(s) like:

"genisoimage: Error:
./ubuntu/pool/main/g/golang-gogoprotobuf/golang-gogoprotobuf\
-dev_0.0~git20150828.0.6cab0cc-1~u14.04+mos1_arm64.deb and
./ubuntu/pool/main/g/golang-gogoprotobuf/golang-gogoprotobuf\
-dev_0.0~git20150828.0.6cab0cc-1~u14.04+mos1_amd64.deb
have the same Joliet name"

[1] https://gerrit.opnfv.org/gerrit/#/c/14973/

Change-Id: If58a18ba46343a52ce6e9a0a6a0482c1a3079451
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>