arm support for new linuxthreads in 0.9.29

[Hamish Moffatt]

Hi,

I'm trying to upgrade to 0.9.29 and use the new linuxthreads, but my
target is arm and it won't compile due to missing sysdep-cancel.h.

Attempts to drop in versions thereof from glibc's code result in
successful compilation, but any threaded application segfaults during
startup. 

Switching back to the old linuxthreads works, but I'm having problems
with a multithreaded application hanging so I want to try the new
library... What do I need to do to get the new version to compile?

thanks
Hamish
-- 
Hamish Moffatt VK3SB <hamish at debian.org> <hamish at cloud.net.au>