While at it, add -t to --help, and fix comments which say that -t is ignored
function old new delta
packed_usage 32427 32444 +17
umount_main 558 552 -6
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(add/remove: 0/0 grow/shrink: 1/1 up/down: 17/-6) Total: 11 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>