Fix: ISO build omits long path files

Fix: ISO build omits long path files

make iso generates:
libisofs: WARNING : File "/ubuntu/pool/main/libj/\
libjs-twitter-bootstrap-datepicker/libjs-twitter-bootstrap-\
datepicker_1.3.1+dfsg1-1~u14.04+mos1_all.deb" can't be added
to Joliet tree, because its path length is larger than 240

At the end this package is missing in latest ISO.
NOTE: This issue is only triggered on certain kernels during build.

Closes-bug: FUEL-190

Change-Id: I21f7f1cbe3f64317d2feb66e371611a654cf30f8
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>