Set fixed allocation pools for tests that uses fixed IPs

Neutron may allocate additional IPs for internal services
which may conflict with hardcoded IPs in the tests. To avoid
this rase set allocation pool explicitly to do not overlap
with fixed_ip_address specified in the test

Change-Id: I6a5b32cba632b396d18b394061c669eb9d4e10d7
2 files changed