[plugins] auth: compile fix when no PAM support is available
[plugins] auth: compile fix when no PAM support is available

christianparpart/x0,xzero/x0,christianparpart/x0,xzero/x0,christianparpart/x0,xzero/x0,christianparpart/x0,xzero/x0,xzero/x0,christianparpart/x0,christianparpart/x0,xzero/x0,christianparpart/x0