Fix e2fsck, debugfs, and the ext2fs_mkdir function so that when we create

Fix e2fsck, debugfs, and the ext2fs_mkdir function so that when we create
a new inode we make sure that the extra information in the inode (any extra
fields in a large inode and any ea-in-inode information) is cleared.  This
can happen when e2fsck creates a new root inode or a new lost+found directory,
or when the user uses the debugfs write, mknod, or mkdir commands.  Otherwise,
the newly create inode could inherit garbage (or old EA information) from
a previously deleted inode.