cacheline_aligned is a special section. It cannot be const at the same
time because it's not read-only. It doesn't give any MMU protection.

Mark it ____cacheline_aligned to not place it in a special section,
but just align it in .rodata

Cc: herbert@gondor.apana.org.au
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>