Add fstatat64 support to s390 in order to follow changes with
commit cff2b760096d1e6feaa31948e7af4abbefe47822 .
Also fixes compilation for 31 bit.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>