Fix syntax error in script

One of the recent patches introduced a syntax error in the marconi
script. This patch fixes the issue & gets marconi running in
devstack again.

Change-Id: I46a039f72174c4898869983de03a1e29cbe435bf
Merge "Fix syntax error in script"
Merge branch 'usb-prereq' into dt-test
Merge branch 'conf-tempest' into dt-test