Let other developers know that we have `%pIA` to print `struct ipaddr *`.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
+-----------+--------------------------+----------------------------------------------+
| ``%pI6`` | ``struct in6_addr *`` | ``fe80::1234`` |
+-----------+--------------------------+----------------------------------------------+
+| ``%pIA`` | ``struct ipaddr *`` | ``1.2.3.4`` |
+| | | |
+| | | ``fe80::1234`` |
++-----------+--------------------------+----------------------------------------------+
| ``%pFX`` | ``struct prefix *`` | ``fe80::1234/64`` |
+-----------+--------------------------+----------------------------------------------+
| ``%pSG4`` | ``struct prefix_sg *`` | ``(*,1.2.3.4)`` |