keymgr: proper error handling within del-all-old

src/utils/keymgr/offline_ksk.c

@@ -185,7 +185,9 @@ int keymgr_del_all_old(kdnssec_ctx_t *ctx)
 		knot_kasp_key_t *key = &ctx->zone->keys[i];
 		if (knot_time_cmp(key->timing.remove, ctx->now) < 0) {
 			int ret = kdnssec_delete_key(ctx, key);
-			printf("- %s\n", knot_strerror(ret));
+			if (ret != KNOT_EOK) {
+				return ret;
+			}
 		}
 	}
 	return kdnssec_ctx_commit(ctx);