SVGHMI: changes that should fix some corner cases about unlinking and discardable element that still didn't show until now.
- list that would have been declared in some groups could have been discarded.
- elements to be unlinked were comuted based on filtering $hmi_elements, whereas $hmi_widget already filtered list
<?xml version='1.0' encoding='utf-8'?>
<PyFile xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<variables>
<variable name="PyVar0" type="DINT"/>
<variable name="PyVar1" type="DINT"/>
</variables>
<globals>
<xhtml:p><![CDATA[]]></xhtml:p>
</globals>
<init>
<xhtml:p><![CDATA[]]></xhtml:p>
</init>
<cleanup>
<xhtml:p><![CDATA[]]></xhtml:p>
</cleanup>
<start>
<xhtml:p><![CDATA[]]></xhtml:p>
</start>
<stop>
<xhtml:p><![CDATA[]]></xhtml:p>
</stop>
</PyFile>