Properly query for multiple machine types
Properly query for multiple machine types

...in list_locks()

Signed-off-by: Zack Cerza <f801c831581d4150a2793939287636221d62131e@inktank.com>

ivotron/teuthology,SUSE/teuthology,dmick/teuthology,ceph/teuthology,dreamhost/teuthology,caibo2014/teuthology,yghannam/teuthology,yghannam/teuthology,robbat2/teuthology,t-miyamae/teuthology,ktdreyer/teuthology,ktdreyer/teuthology,michaelsevilla/teuthology,dreamhost/teuthology,SUSE/teuthology,SUSE/teuthology,caibo2014/teuthology,ceph/teuthology,tchaikov/teuthology,tchaikov/teuthology,robbat2/teuthology,dmick/teuthology,zhouyuan/teuthology,michaelsevilla/teuthology,ivotron/teuthology,t-miyamae/teuthology,zhouyuan/teuthology,dmick/teuthology