msi: Do not return success on failure (spotted by clang).

dlls/msi/where.c

@@ -593,7 +593,7 @@ static UINT WHERE_evaluate( MSIWHEREVIEW *wv, const UINT rows[],
 
     default:
         ERR("Invalid expression type\n");
-        break;
+        return ERROR_FUNCTION_FAILED;
     }
 
     return ERROR_SUCCESS;