Fix response when querying host detail by host name

Fix response when querying host detail by host name

When querying host detail by host name like
'wanghao-devstack-snapshot@lvmdriver-1'
returned by host list command, cinder returns
incorrect result in 'total' block.
"resource": {
        "volume_count": "0",
        "total_volume_gb": "0",
        "total_snapshot_gb": "0",
        "project": "(total)",
        "host": "wanghao-devstack-snapshot@lvmdriver-1",
        "snapshot_count": "0"
        }
This issue is caused by 'volume_data_get_for_host'
in sqlalchemy. This has nothing to do with multibackend,
this is due to the introduction of pool support for single
backend.
Fix this by querying volume filter by host or host name
like 'host#%' in volume_data_get_for_host.

Change-Id: I751a474677d50e552d87fe06fadfed45e3c1ddab
Closes-Bug: #1429787