[PATCH] stop_machine.c copyright

I had to look back: this code was extracted from the module.c code in 2005.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>