fs: amended coredump-related sysctl functions

fs: amended coredump-related sysctl functions

This fixes an error introduced in the coredump-header patch in the
coredump removal patch I submitted earlier.  It should be squashed into
that patch series so that the Kconfig option to remove coredump doesn't
cause compile-time errors.

Signed-off-by: Alex Kelly <alex.page.kelly@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>