logfs: get rid of magical inodes

ordering problems at ->kill_sb() time are solved by doing iput()
of these suckers in ->put_super()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/logfs/segment.c

@@ -929,5 +929,4 @@ void logfs_cleanup_areas(struct super_block *sb)
 	for_each_area(i)
 		free_area(super->s_area[i]);
 	free_area(super->s_journal_area);
-	destroy_meta_inode(super->s_mapping_inode);
 }