audit: eliminate audit_enabled magic number comparison

Remove comparison of audit_enabled to magic numbers outside of audit.

Related: https://github.com/linux-audit/audit-kernel/issues/86

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

kernel/audit.c

@@ -83,9 +83,6 @@
 #define AUDIT_INITIALIZED	1
 static int	audit_initialized;
 
-#define AUDIT_OFF	0
-#define AUDIT_ON	1
-#define AUDIT_LOCKED	2
 u32		audit_enabled = AUDIT_OFF;
 bool		audit_ever_enabled = !!AUDIT_OFF;