misc: Fix allocation 'borrowed' by vhost_net

10, 233 is allocated officially to /dev/kmview which is shipping in
Ubuntu and Debian distributions.  vhost_net seem to have borrowed it
without making a proper request and this causes regressions in the other
distributions.

vhost_net can use a dynamic minor so use that instead.  Also update the
file with a comment to try and avoid future misunderstandings.

cc: stable@kernel.org
Signed-off-by: Alan Cox <device@lanana.org>
[ We should have caught this before 2.6.34 got released.  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>