Handle bswap on ram directly in load/store_helper. This fixes a
bug with the previous implementation in that one cannot use the
I/O path for RAM.
Fixes: a26fc6f515
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>