libxml2's more recent versions don't have xml2-config anymore

Reported by Julien Puydt

no_more_xml2_config.patch (7.24 KB, text/plain)

Patch taking care of part (2) of the solution

Libxml2's more recent versions don't have xml2-config anymore, so the configure script won't see them at all.

To get around it, I propose to (1) drop m4/libxml2.m4, and (2) apply the attached patch, which fixes configure.ac and the Makefile.am files.