Refactor: tools: Functionize cibadmin command handling

This is too monolithic currently. This is just a stepping stone to make
future work easier to review.

No real code changes except for moving a couple of variables and
changing cmd_info->cib_request to just cib_request in the
cib_internal_op() call.

Signed-off-by: Reid Wahl <nrwahl@protonmail.com>