libcgicc: fix build breakage and bump version

libcgicc: fix build breakage and bump version

First, the build was failing with:

cd .. && /bin/sh /home/test/brbuild/build/cgicc-3.2.7/support/missing --run autoheader
/home/test/brbuild/build/cgicc-3.2.7/support/missing: line 52: autoheader: command not found
WARNING: `autoheader' is missing on your system.  You should only need it if
         you modified `acconfig.h' or `configure.ac'.  You might want
         to install the `Autoconf' and `GNU m4' packages.  Grab them
         from any GNU archive site.

That was because the PATH doesn't contain $(HOST_DIR)/usr/bin. So we
pass $(TARGET_MAKE_ENV) when calling make.

Then, the build was failing because of the crappy configure.ac and
doc/Makefile.am this project has. configure.ac checks if doxygen is
available, and if it isn't, it sets DOXYGEN to /bin/echo. Then,
doc/Makefile.am does:

        DATE=`date '+%-d %b %Y'` VERSION=$(VERSION) $(DOXYGEN) Doxyfile
        cp $(IMAGES) cgicc-doc.css html
        mv html/index.html html/index.html.bak

When DOXYGEN=/bin/echo, then the first line does not generate anything
in html/, and the third line fails.

Therefore, we add a patch that allows to pass a --disable-doc option,
which removes the check for Doxygen. If --enable-doc is passed, then
the configure script fails if Doxygen isn't found (but in the
Buildroot case, we always pass --disable-doc to avoid the doxygen
dependency).

We also take this opportunity to bump the version of libcgicc, and to
remove a patch that is no longer needed due to this version bump.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>