Misc: Primitive model: Use crm_resource --show-metadata

crm_resource supports --show-metadata since pacemaker 1.1.8.  We
were using lrmd_test with a fallback to lrmadmin, but since the
former is now packaged in pacemaker-cts, the latter is long gone
and we require pacemaker 1.1.8+ anyway, we should be doing this
the clean way by invoking crm_resource.

Signed-off-by: Tim Serong <tserong@suse.com>