* src/storage/storage_backend_mpath.c (virStorageBackendIsMultipath):
The result of dm_get_next_target was never used (and isn't needed),
so don't store it.
The virConnectPtr is no longer required for error reporting since
that is recorded in a thread local. Remove use of virConnectPtr
from all APIs in storage_conf.{h,c} and storage_encryption_conf.{h,c}
and update all callers to match
