Cleanup sysctl

There has not been much maintenance on sysctl in years, and as a result is
there is a lot to do to allow future interesting work to happen, and being
ambitious I'm trying to do it all at once :)

The patches in this series fall into several general categories.

- Removal of useless attempts to override the standard sysctls

- Registers of sysctl numbers in sysctl.h so someone else does not use
  the magic number and conflict.

- C99 conversions so it becomes possible to change the layout of 
  struct ctl_table without breaking everything.

- Removal of useless claims of module ownership, in the proc dir entries

- Removal of sys_sysctl support where people had used conflicting sysctl
  numbers. Trying to break glibc or other applications by changing the
  ABI is not cool.  9 instances of this in the kernel seems a little
  extreme.

- General enhancements when I got the junk I could see out.

Odds are I missed something, most of the cleanups are simply a result of
me working on the sysctl core and glancing at the users and going: What?

Eric