MIPS: N32: Fix getdents64 syscall for n32

MIPS: N32: Fix getdents64 syscall for n32

Commit 31c984a5acabea5d8c7224dc226453022be46f33 introduced a new syscall
getdents64. However, in the syscall table, the new syscall still refers to
the old getdents which doesn't work.

The problem appeared with a system that uses the eglibc 2.12-r11187 (that
utilizes that new syscall) is very confused. The fix has been tested with
that eglibc version.

Signed-off-by: Bernhard Walle <walle@corscience.de>
To: linux-mips@linux-mips.org
Cc: ddaney@caviumnetworks.com
Cc: akpm@linux-foundation.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1567/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>