XPath default root node is the document element (not the document itself)
XPath default root node is the document element (not the document itself)

fixes https://github.com/peachpiecompiler/peachpie/issues/463

iolevel/peachpie,iolevel/peachpie-concept,peachpiecompiler/peachpie,peachpiecompiler/peachpie,iolevel/peachpie,peachpiecompiler/peachpie,iolevel/peachpie-concept,iolevel/peachpie,iolevel/peachpie-concept