If libz or liblzma are detected with pkg-config, AC_CHECK_HEADERS must
not be run because the correct CPPFLAGS aren't set. It is actually not
required have separate checks for LIBXML_ZLIB_ENABLED and HAVE_ZLIB_H.
Only check for LIBXML_ZLIB_ENABLED and remove HAVE_ZLIB_H macro.
Fixes bug 764657, bug 787041.
* config.h.in configure.in nanoftp.c nanohttp.c xmllint.c
macos/src/config-mac.h: use XML_SOCKLEN_T instead of SOCKLEN_T
since apparently IBM can't avoid breaking common defines #166922
Daniel
* configure.in libxml.h parser.c testThreads.c macos/: integrated
Eric Lavigne (sp???) contribution to build libxml2 on MacOS using
CodeWarrior.
Daniel