RFC: *_FOR_TARGET and friends

[Aldy Hernandez]

I usually build my cross builds with a combined tree or with an
uberbaum.  This time I decided to build binutils separately and
install it.  This should work.

However, the $$ escaping doesn't work.  We end up just calling "sed
-e".  Has no one run into this?  I've tried a variety of make versions
on my Linux box.

The problem is here:

       t='$(program_transform_name)'; echo ar | sed -e $$t ; \
                                                       ^^^
						       ^^^

This, at least on my make, should be $$$$t.  Same thing goes for
RANLIB_FOR_TARGET and NM_FOR_TARGET.

If so, I can supply a patch.

Cheers.
Aldy