Fix of the next problem:

If the same dita topic is placed into ditalist and htmllist, topic will
not put to the temp folder and as a result will not published. 
The problem occures when `<xref>` link has "format" attribute with non
"dita" value, and not "html" value. 
In our case  we have next self-referenced link:
```xml
<xref format="Figure and Page"
href="#Assembling_the_Antenna_1/WRM_CHDGFBHA">Installing Limit Switch
Counterpart</xref>
```
Due non standard format value this topic was placed to the htmllist, and
as a result was not publish, despite it was also placed to the ditalist.
From our point of view the logic has to be next: if topic was marked as
"dita" it has to be moved to the temp folder for further publication,
regardless it was also marked as "html".