correct_password: explain in detail why it is ok to use bb_banner
fsck_minix: make it print bb version, not it's own (outdated/irrelevant) one
Marginal size difference:
text data bss dec hex filename
679119 2700 15632 697451 aa46b busybox_old
679091 2700 15632 697423 aa44f busybox_unstripped