AUDIT: Fix definition of audit_log_start() if audit not enabled

audit_log_start() seems to take 3 arguments, but its defined to take 
only 2 when AUDIT is turned off.

security/selinux/avc.c:553:75: macro "audit_log_start" passed 3 arguments, but takes just 2

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 38999f8..c22405f 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -286,7 +286,7 @@
 extern struct semaphore audit_netlink_sem;
 #else
 #define audit_log(c,t,f,...) do { ; } while (0)
-#define audit_log_start(c,t) ({ NULL; })
+#define audit_log_start(c,g,t) ({ NULL; })
 #define audit_log_vformat(b,f,a) do { ; } while (0)
 #define audit_log_format(b,f,...) do { ; } while (0)
 #define audit_log_end(b) do { ; } while (0)