main: Extend read_stdin() to accept hidden (password) input
main: Extend read_stdin() to accept hidden (password) input

We can use read_stdin() for all of our prompts, instead of duplicating
the fgets()/strchr()/... logic everywhere user input is needed.

Signed-off-by: Kevin Cernekee <3105dbb3dd63fbb4f6371cfb04adc6726f76c56b@gmail.com>

don-johnny/openconnect,matlockx/openconnect,cernekee/openconnect,neshema/openconnect,cernekee/openconnect,liiir1985/openconnect,chadcatlett/openconnect,atyndall/openconnect,chadcatlett/openconnect,matlockx/openconnect,lins05/openconnect,mveplus/openconnect-client,don-johnny/openconnect,atyndall/openconnect,matlockx/openconnect,neshema/openconnect,brandt/openconnect,nmav/openconnect-mine,brandt/openconnect,mtmiller/openconnect,liiir1985/openconnect,matlockx/openconnect,don-johnny/openconnect,lins05/openconnect,mtmiller/openconnect,cernekee/openconnect,cernekee/openconnect,nmav/openconnect-mine,liiir1985/openconnect,don-johnny/openconnect,nmav/openconnect-mine,chadcatlett/openconnect,neshema/openconnect,brandt/openconnect,lins05/openconnect,mtmiller/openconnect,liiir1985/openconnect,mveplus/openconnect-client,atyndall/openconnect,nmav/openconnect-mine,mtmiller/openconnect,chadcatlett/openconnect,brandt/openconnect,mveplus/openconnect-client,neshema/openconnect,atyndall/openconnect,mveplus/openconnect-client,lins05/openconnect