luci-base: Fix addr:port validate always fails

In cbi.js there is an error which causes ipaddrport validation to always fail.
JS match() return the entire match as ret[0] and individual matches (for multiple ()) as the
subsequent list members.  So we fix it by just fixing the index in the calls that want the
individual parts.

Signed-off-by: Daniel F. Dickinson <cshored@thecshore.com>