sanitize audit_ipc_obj()

* get rid of allocations
* make it return void
* simplify callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/ipc/shm.c b/ipc/shm.c
index 38a0557..57dd500 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -747,9 +747,7 @@
 			goto out;
 		}
 
-		err = audit_ipc_obj(&(shp->shm_perm));
-		if (err)
-			goto out_unlock;
+		audit_ipc_obj(&(shp->shm_perm));
 
 		if (!capable(CAP_IPC_LOCK)) {
 			uid_t euid = current_euid();