tar: fix "tar -cJ" ignoring -J option. closes 7706

function                                             old     new   delta
tar_main                                             895     938     +43
vfork_compressor                                     206     191     -15
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(add/remove: 0/0 grow/shrink: 1/1 up/down: 43/-15)             Total: 28 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed