[cairo] building OSX target from git clone

[Christian Biesinger]

Nicolas Setton wrote:
>  - copy files that would have been generated by autogen.sh from the 
> release tarball (ie, the "configure" script, the files "Makefile.in" in 
> various dirs, "libtool", "install-sh" and a few others)

That doesn't necessarily work... there may have been changes to 
configure.in/Makefile.am since the release, in which case those 
generated files would be outdated.