If the AP is running older legacy WiNG 4 firmware (v4.3.1), there is no CLI. CLI was introduced once AP is upgraded to WiNG 5. If APs are adopting to site controller via L2, these APs would not have an IP.
Not sure what version you are trying to upgrade to, but the AP needs to be upgraded to v5.2.13 first, before moving forward to a more current release.