[coreboot] cpu/amd/car/post_cache_as_ram.c: Build problems with GCC 4.8.x: `error: bp cannot be used in asm here`

[ron minnich]

Paul, nice work!

Stefan and I have had a lot of discussions about inline asm over the
years. We both dislike it and would be very happy to get patches that
got rid of it! [hint hint!]. It's been a never ending stream of
problems.

Thanks, very interesting.

ron