arch: sparc: Override struct __kernel_old_timeval

struct __kernel_old_timeval is supposed to have the same
layout as struct timeval. But, it was inadvarently missed
that __kernel_suseconds has a different definition for
sparc64.
Provide an asm-specific override that fixes it.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Cc: sparclinux@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>