f2fs: fix command-line options

f2fstat didn't work because it allways suposed invalid option due to
a problem with getopt(). The fix has been applied to all modules.

Also, main function on mkfs.f2fs has been renamed from make_f2fs_main to
mkfs_f2fs_main by coherence.
f2fs: create dump.f2fs symlink
f2fs: show version on all tools