fsck.f2fs: show ckeckpoint version info
fsck.f2fs: show ckeckpoint version info

This patch shows the valid checkpoint version number.

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

Euphoria-OS-Legacy/android_external_f2fs-tools,Fusion-Rom/android_external_f2fs-tools,VanirAOSP/external_f2fs-tools,Fusion-Rom/android_external_f2fs-tools,VanirAOSP/external_f2fs-tools,Euphoria-OS-Legacy/android_external_f2fs-tools