The project has migrated from www.xmlsoft.org to gitlab.gnome.org.
Update the homepage accordingly, and use gnomebase to construct the
download URL, rather than including it in SRC_URI explicitly.
Note that the download is now in .xz format rather than .gz, so the
sha256sum is updated accordingly. Post-decompression tarballs are
identical, so there is no change to the libxml2 code.
Signed-off-by: Ralph Siemsen <ralph.siemsen@linaro.org> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
