sh: syscall 300 should be __NR_fstatat64.

syscall number 300 fails while testing with latest LTP
(ltp-full-20061121.tgz) on sh.

sys_fstatat64 is called on syscall 300 (see arch/sh/kernel/syscalls.S),
and __ARCH_WANT_STAT64 is defined in include/asm-sh/unistd.h, so
following patch seems correct.

Signed-off-by: SUGIOKA Toshinobu <sugioka@itonet.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>