libstdc++-v3/ChangeLog:

	* doc/xml/manual/status_cxx2011.xml: Update std::call_once
	status.
	* doc/xml/manual/status_cxx2014.xml: Likewise.
	* doc/xml/manual/status_cxx2017.xml: Likewise. Update
	std::from_chars and std::to_chars status. Fix formatting.
	* doc/html/manual/status.html: Regenerate.

Committed to trunk.