modprobe-small: make string buffer code robust; fix help text

together with previous one-liner:

function                                             old     new   delta
append                                                70      99     +29
parse_module                                         295     311     +16
copy_stringbuf                                        35      36      +1
packed_usage                                       26545   26540      -5
appendc                                               27       -     -27
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(add/remove: 0/1 grow/shrink: 3/1 up/down: 46/-32)             Total: 14 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2 files changed