Fix inventory vars containing spaces

Some clouds have availability zones with spaces in their
names. Currently zuul generates something like this as ansible
inventory:

node nodepool_region=None (...) nodepool_az=Failure domain 1

This breaks ansible when trying to read the inventory. Quoting the
inventory variable values solves this issue.

Change-Id: I3e97f40986689b3779efc448eb0d5f1db009e796
1 file changed