Reviewed-By: Julien Cristau <jcristau@debian.org>
(cherry picked from commit d2fb6f56)

Set TZ=UTC before calling asciidoc to make the embedded dates invariant
to timezones in order to make the package build reproducibly.

We ship the EGL-aware application es2_info in mesa-utils-extra.

We are shipping nouveau_dri.so in libgl1-mesa-dri and we dropped the
package libgl1-mesa-dri-experimental.

(Backport uploaded.)

In case somebody's interested in e.g. the headers, ship everything
under /usr (since we already have /usr/lib/… for the shared objects).

Let's try and document the specific handling of sid+experimental
packages for server+drivers.