lib/cli: reduce strcmp in CLI hot paths

lib/cli: reduce strcmp in CLI hot paths

Er, no idea how anyone could ever have thought that it would be a good
idea to have a zillion of strcmp() calls in the CLI's active paths, just
to compare against things like "A.B.C.D".

Reduces 40k prefix list load time from 1.65s to 1.23s (1.34:1).

Acked-by: Paul Jakma <paul@jakma.org>
[v2: killed CMDS_* macros]
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
(cherry picked from commit 10bac80195cf5a781da6e4415e6580fd7080f734)