fix: use proper hostplatform variable, now host attributes really aren't empty on windows recipes.
<?xml version="1.0"?>
<SystemDefinition name="MCL" schema="1.4.0">
<systemModel>
<layer name="common">
<module name="allexports">
<component name="envelope">
<unit unitID="001" name="emime" bldFile="common/generic/app-framework/emime/group"/>
<unit unitID="001" name="featreg" bldFile="common/generic/syslibs/ezlib/group"/>
<unit unitID="001" name="caf" bldFile="common/generic/syslibs/caf2/group"/>
<unit unitID="001" name="charconv" bldFile="common/generic/syslibs/charconv/ongoing/group/"/>
<unit unitID="001" name="featreg" bldFile="common/generic/syslibs/featreg/group"/>
<unit unitID="001" name="store" bldFile="common/generic/syslibs/store/group"/>
</component>
</module>
</layer>
</systemModel>
<build>
</build>
</SystemDefinition>