losetup: support -f (Loic Grenie <loic.grenie@gmail.com>)

function                                             old     new   delta
losetup_main                                         238     278     +40
packed_usage                                       23021   23027      +6
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(add/remove: 0/0 grow/shrink: 2/0 up/down: 46/0)               Total: 46 bytes

2 files changed