libstdc++: Adjust whitespace in status tables in manual

This simplifies the changes needed after branching for a new release, so
that new line breaks don't need to be introduced every time we branch.

libstdc++-v3/ChangeLog:

	* doc/html/manual/status.html: Regenerate.
	* doc/xml/manual/status_cxx1998.xml: Adjust whitespace.
	* doc/xml/manual/status_cxx2011.xml: Likewise.
	* doc/xml/manual/status_cxx2014.xml: Likewise.
	* doc/xml/manual/status_cxx2017.xml: Likewise.
	* doc/xml/manual/status_cxx2020.xml: Likewise.
	* doc/xml/manual/status_cxx2023.xml: Likewise.
	* doc/xml/manual/status_cxxtr1.xml: Likewise.
	* doc/xml/manual/status_cxxtr24733.xml: Likewise.