Fixed zealous GCC warning. (#8355)

Amend dfd1bc3

imgui_tables.cpp

@@ -1052,7 +1052,7 @@ void ImGui::TableUpdateLayout(ImGuiTable* table)
         ImGuiTableColumn* column = &table->Columns[column_n];
 
         // Initial nav layer: using FreezeRowsCount, NOT FreezeRowsRequest, so Header line changes layer when frozen
-        column->NavLayerCurrent = (ImS8)(table->FreezeRowsCount > 0 ? ImGuiNavLayer_Menu : table->NavLayer);
+        column->NavLayerCurrent = (ImS8)(table->FreezeRowsCount > 0 ? ImGuiNavLayer_Menu : (ImGuiNavLayer)table->NavLayer);
 
         if (offset_x_frozen && table->FreezeColumnsCount == visible_n)
         {