new read-only plt format

[Richard Henderson]

Apparently SElinux really really doesn't like writable code.  Alan
Modra recently spent a bunch of time redesigning powerpc32 to cope
with this restriction.

It was quite a bit easier for alpha; implementable over a long weekend.
Checked in to head glibc and binutils is support for a new read-only
plt format.  

So if folk are actively working on FC4, I'd appreciate it if they'd 
give the new code a try.



r~