Add configure-time tools to the 'host_tools' target

Rebuild configure-time tools within the 'host_tools' meta target.

Pick-to: 6.5
Task-number: QTBUG-109792
Change-Id: I1bd69c8e71185b6ec236c0f32064ba8f2c9f5ab0
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Jörg Bornemann <joerg.bornemann@qt.io>

cmake/QtToolHelpers.cmake

@@ -646,6 +646,10 @@ function(qt_internal_add_configure_time_tool target_name)
         ${unparsed_arguments}
     )
 
+    if(TARGET host_tools)
+        add_dependencies(host_tools "${target_name}_build")
+    endif()
+
     if(NOT arg_NO_INSTALL AND arg_TOOLS_TARGET)
         qt_internal_add_targets_to_additional_targets_export_file(
             TARGETS ${target_name}