*context powerpc patches

I see the glibc patches for the context stuff,
they're added to an already present set for
powerpc64, which have been in the glibc
2.3 tree, but not the 2.2 tree.

Somebody needs to tell me whether we're
going to issue an lsbsi for ppc64 based
on the current 2.2.5 source base, if so
those bits are going to have to be added also.
Is that a separate patch for "when it happens",
or should I think about them for now.

Lest it be unclear, I'd be happier if someone
who understood the ppc32 would prepare
the patch for the lsbsi, as there may be
other files affected beyond the four assembler
and one header file that seem to have just
been added.

-- mats