Patch from Andries.Brouwer@cwi.nl

Now that 2.5.65 is out, the next dev_t patch.  It was a bit large and
unreadable, so I split it into three clean pieces.  Afterwards, since many
people ask for this, a fourth patch that actually changes the type of dev_t
(not to be applied yet, that is just for playing).

The first patch is the cdev-kill patch that I sent out earlier.  It is no use
having two forms of chardev registration in the source, and my version of the
path of small modifications does not pass through this version, although the
final result will not be that different.  So, kill cdev_cachep,
cdev_cache_init, cdfind, cdget, cdput, inode->i_cdev, struct char_device.
All of this is dead code today.

The second patch removes MAX_CHRDEV.

The third patch polishes linux/major.h.