optimize openbsd pkg_mgr fact discovery

lib/ansible/module_utils/facts.py

@@ -334,12 +334,13 @@ class Facts(object):
                     self.facts[factname] = keydata.split()[1]
 
     def get_pkg_mgr_facts(self):
-        self.facts['pkg_mgr'] = 'unknown'
-        for pkg in Facts.PKG_MGRS:
-            if os.path.exists(pkg['path']):
-                self.facts['pkg_mgr'] = pkg['name']
         if self.facts['system'] == 'OpenBSD':
                 self.facts['pkg_mgr'] = 'openbsd_pkg'
+        else:
+            self.facts['pkg_mgr'] = 'unknown'
+            for pkg in Facts.PKG_MGRS:
+                if os.path.exists(pkg['path']):
+                    self.facts['pkg_mgr'] = pkg['name']
 
     def get_service_mgr_facts(self):
         #TODO: detect more custom init setups like bootscripts, dmd, s6, Epoch, runit, etc