SVGHMI: widgets are not anymore binary relative or absolute, but have a "relativeness".
Because of allowing multiple variables per widget, we must distinguish if individual variables is relative to page, not the whole widget.
<xsd:element name="Xenomai">
<xsd:complexType>
%(toolchain_gcc)s
<xsd:attribute name="XenoConfig" type="xsd:string" use="optional" default="xeno-config"/>
</xsd:complexType>
</xsd:element>