Here's a small set of patches that switch the code to use C99
desiginated initializers. Patches are against 2.5.42.

Make the 144 files in fs/ that need it include buffer_head.h directly.
Again some uses in the VFS files are layering violations and need to
be addressed later.  The new include statement gives a nice grep pattern
for that :)

Originally by Grant R.Guenther
Has had a quick once over by Al, who weeded out one chunk that was
unrelated.

Big bits first, I'll redo the smaller bits tomorrow after some sleep.
Same as last time, rediffed against pre5

- Al Viro: floppy_eject cleanup, mount cleanups
- Jens Axboe: bio updates
- Ingo Molnar: mempool fixes
- GOTO Masanori: Fix O_DIRECT error handling