selinux: Delete an unnecessary return statement in cond_compute_av()

The script "checkpatch.pl" pointed information out like the following.

WARNING: void function return statements are not generally useful

Thus remove such a statement in the affected function.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paul Moore <paul@paul-moore.com>

security/selinux/ss/conditional.c

@@ -664,5 +664,4 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
 				(node->key.specified & AVTAB_XPERMS))
 			services_compute_xperms_drivers(xperms, node);
 	}
-	return;
 }