Revert "f2fs: fix to do sanity check on direct node in truncate_dnode()"

This reverts commit a78a8bcd which is
commit a6ec8378 upstream.

Something is currently broken in the f2fs code, Guenter has reported
boot problems with it for a few releases now, so revert the most recent
f2fs changes in the hope to get this back to a working filesystem.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/b392e1a8-b987-4993-bd45-035db9415a6e@roeck-us.net


Cc: Chao Yu <chao@kernel.org>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>