Update CBT to support RBD Erasure Coding testing

[acalhounRH]

CBT current does not support testing RBD Erasure coding (ceph 12.2.2). ceph.py needs to be updated such that when librbdfio.py calls mkpool with a data pool specified ceph.py uses the data_pool_profile instead of the pool_profile.

Since librbdfio will append "-data" to the pool name if a user had specified a data_pool the below could be a possible solution.

cbt/cluster/ceph.py:
def mkpool(self, name, profile_name, application, base_name=None):
if 'data' in name:
pool_profiles = self.config.get('data_pool_profiles', {'default': {}})
else:
pool_profiles = self.config.get('pool_profiles', {'default': {}})
. . .