xxd: fix printing of trailing spaces

function                                             old     new   delta
bb_dump_dump                                        1497    1523     +26
xxd_main                                             459     466      +7
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(add/remove: 0/0 grow/shrink: 2/0 up/down: 33/0)               Total: 33 bytes

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