lvm: Enhance lvm performance by altering filter

Change-Id: If92940f132238d90e91c1e9ddfecb68df453e1d8
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=981055
Signed-off-by: Yeela Kaplan <ykaplan@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/16730
Reviewed-by: Marina Kalinin <marinamku@gmail.com>
Tested-by: Marina Kalinin <marinamku@gmail.com>
Reviewed-by: Saggi Mizrahi <smizrahi@redhat.com>