mkfs.f2fs: support <1% overprovision ratio

Big partition size needs uner 1% overprovision space to acquire more space.

    section  ovp ratio  ovp size
For 8TB,
    -s1    : 0.07%     -> 10GB
    -s32   : 0.39%     -> 65GB
    -s64   : 0.55%     -> 92GB
    -s128  : 0.78%     -> 132GB

For 128GB,
    -s1    : 0.55%     -> 1.4GB
    -s32   : 3.14%     -> 8GB
    -s64   : 4.45%     -> 12GB
    -s128  : 6.32%     -> 17GB

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
3 files changed