regression: bfs endianness bug

BFS_FILEBLOCKS() expects struct bfs_inode * (on-disk data, with little-
endian fields), not struct bfs_inode_info * (in-core stuff, with host-
endian ones).

It's a macro and fields with the right names are present in
bfs_inode_info, so it compiles, but on big-endian host it gives bogus
results.

Introduced in commit f433dc56

 ("Fixes to
the BFS filesystem driver").

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