ci: Move docker images from Debian buster to bullseye

Among other things, this gets us GCC 10 (was 6).

Requires some changes to third party components we use:

* Install apitrace (& waffle) from Debian; was hitting issues with the
  local build, and it's the same version 9.0 anyway.
* Update Fossilize to a newer commit which builds with GCC 10.
* apt.llvm.org repositories are no longer needed.
* Use an SPIRV-LLVM-Translator commit which builds with LLVM 11.0.1.
* Install XCB packages from Debian, 1.13 fails to build with Python 3.9.
* Install wayland-protocols from Debian, 1.12 is too old for
  libgtk-3-dev in bullseye.

LLVM 7/8 packages are no longer available.

Also adapt expected test results to Xvfb now exposing multi-samle
GLXFBConfigs.

v2:
* Install clang instead of clang-11.

Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/3124
Reviewed-by: Eric Anholt <eric@anholt.net> # v1
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9833>

.gitlab-ci/container/build-apitrace.sh

@@ -1,36 +0,0 @@
-#!/bin/bash
-
-set -ex
-
-# Need an unreleased version of Waffle for surfaceless support in apitrace
-# Replace this build with the Debian package once that's possible
-
-WAFFLE_VERSION="e3c995d9a2693b687501715b6550619922346089"
-git clone https://gitlab.freedesktop.org/mesa/waffle.git --single-branch --no-checkout /waffle
-pushd /waffle
-git checkout "$WAFFLE_VERSION"
-cmake -S . -B _build -DCMAKE_INSTALL_LIBDIR=lib -DCMAKE_BUILD_TYPE=Release $EXTRA_CMAKE_ARGS
-make -C _build install
-mkdir -p build/lib build/bin
-cp _build/lib/libwaffle-1.so build/lib/libwaffle-1.so.0
-cp _build/bin/wflinfo build/bin/wflinfo
-${STRIP_CMD:-strip} build/lib/* build/bin/*
-find . -not -path './build' -not -path './build/*' -delete
-popd
-
-APITRACE_VERSION="9.0"
-
-git clone https://github.com/apitrace/apitrace.git --single-branch --no-checkout /apitrace
-pushd /apitrace
-git checkout "$APITRACE_VERSION"
-# Note: The cmake stuff for waffle in apitrace fails to use waffle's library
-# directory.  Just force the issue here.
-env LDFLAGS="-L/usr/local/lib" \
-    cmake -S . -B _build -G Ninja -DCMAKE_BUILD_TYPE=Release -DENABLE_GUI=False -DENABLE_WAFFLE=on -DWaffle_DIR=/usr/local/lib/cmake/Waffle/ $EXTRA_CMAKE_ARGS
-ninja -C _build
-mkdir build
-cp _build/apitrace build
-cp _build/eglretrace build
-${STRIP_CMD:-strip} build/*
-find . -not -path './build' -not -path './build/*' -delete
-popd