fsck.f2fs: avoid build warning
fsck.f2fs: avoid build warning

Signed-off-by: Jaegeuk Kim <71255387a32c360dfbe6dfb7aaeb123bf1dc8cb6@kernel.org>

seamlik/f2fs-tools,seamlik/f2fs-tools,TurboROM/external_f2fs-tools,TurboROM/external_f2fs-tools