Fix node hang (infinite loop) possible when input_thread() is terminated before

answer() set online to ON_REMOTE. This should resolve the issue with SSH brute
force password attackers hanging nodes in "new user applying for access".
The actual fix was to remove the set of the online variable to ON_REMOTE
in answer() (it's initialized to this value in the sbbs_t constructor), the
check in getkey() is just for extra paranoia and should not be necessary.