audit: Add generic compat syscall support

lib/audit.c provides a generic function for auditing system calls.
This patch extends it for compat syscall support on bi-architectures
(32/64-bit) by adding lib/compat_audit.c.
What is required to support this feature are:
 * add asm/unistd32.h for compat system call names
 * select CONFIG_AUDIT_ARCH_COMPAT_GENERIC

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

diff --cc include/linux/audit.h
Simple merge

diff --cc include/uapi/linux/audit.h
Simple merge

diff --cc lib/Kconfig
Simple merge

diff --cc lib/Makefile
Simple merge

diff --cc lib/audit.c
Simple merge

diff --cc lib/compat_audit.c
Simple merge