PATCH: Add x32 fallocate/posix_fadvise/posix_fallocate

[Roland McGrath]

There seem to be a bunch of these coming up.  Repeating a one-off hack for
every one does not feel right.

All of these are cases where every x32 kernel has the syscalls in question,
even though some other machines' Linux kernels might not.  So while we have
individual .c files now for all these, they could be handled by a mechanism
like syscalls.list for configurations where every supported kernel has the
calls.

I think that's the right thing to do.  Soup up syscalls.list with a way to
mark calls (or particular arguments and return value individually) as
needing full words.  Then you can just add a linux/x32/syscalls.list to
cover all of them.


Thanks,
Roland