This old prompt used to be sent for any login scripts (e.g. QWKnet
via dial-up) that would key off that WWIV-like "name or number"
(NN:) prompt, but was removed (accidentally?) in commit fedabb0b.

Send "NN: " and "PW: " (include the trailing space, just in case), and use
carriage return to move back (and overwrite) rather than 4 backspaces.