This adds the initial support for using autoconf configuration. Support
is available for shared Xlib driver builds. Later this will be extended
to dri and osmesa-only builds and possibly targetting non-X backends.
Support for static library builds will also be added.
The configure script fills in the autoconf config. This is then used by
running `make autoconf' after ./configure.
Testing has been done on Linux/GNU. The configure script tries to
faithfully reproduce the current configs/linux* and configs/freebsd*.
Other platforms can be handled later by adding similar statements and
feature tests.
Pkg-config is used to search for packages when possible. This makes the
build much more flexible and robust to the user's configuration. This
requires that the pkg-config autoconf macros pkg.m4 are included in
aclocal.m4. This requires autoconf and aclocal from autoconf and
automake, respectively.
Dan Nicholson
Michel Dänzer