cpio: allow cpio -i to take params - names of files to extract

Also, improve help text

function                                             old     new   delta
packed_usage                                       28028   28035      +7
cpio_main                                            542     532     -10
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(add/remove: 0/0 grow/shrink: 1/1 up/down: 7/-10)              Total: -3 bytes

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