Fix highlighting of Makefile.inc by adding priority to makefile.xml
Fix highlighting of Makefile.inc by adding priority to makefile.xml

Summary:
Otherwise "Makefile.inc" files will be highlighted as PHP (HTML) which
appears to have priority=10 for *.inc files

Reviewers: #kate, #framework_syntax_hightlighting, vkrause

Reviewed By: #framework_syntax_hightlighting, vkrause

Differential Revision: https://phabricator.kde.org/D3675

janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting,janusw/syntax-highlighting