remove obsolete references to powertweak

This tool hasn't been maintained in over a decade, and is pretty much
useless these days.  Let's pretend it never happened.

Also remove a long-dead email address.

Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
3 files changed