CI: Upgrade kernel to v5.14

Older kernels cannot be built and booted with GCC 10+, as included in
Debian bullseye, due to unfortunate stack-canary issues:
    https://lore.kernel.org/lkml/20200314164451.346497-1-slyfox@gentoo.org/T/

Upgrade to the last-released kernel, 5.14, to fix this.

Signed-off-by: Daniel Stone <daniels@collabora.com>

.gitlab-ci.yml

@@ -43,7 +43,7 @@
 variables:
   FDO_UPSTREAM_REPO: wayland/weston
   FDO_REPO_SUFFIX: "$BUILD_OS/$BUILD_ARCH"
-  FDO_DISTRIBUTION_TAG: '2021-09-14.2'
+  FDO_DISTRIBUTION_TAG: '2021-11-24.0-kernel-v5.14'
 
 
 include:

.gitlab-ci/build-deps.sh

@@ -48,7 +48,7 @@ pip3 install sphinx_rtd_theme==0.4.3 --user
 # The fork pulls in this support from the original GitHub PR, rebased on top of
 # a newer upstream version which fixes AArch64 support.
 if [[ -n "$KERNEL_DEFCONFIG" ]]; then
-	git clone --depth=1 --branch=drm-next-2020-06-11-1 https://anongit.freedesktop.org/git/drm/drm.git linux
+	git clone --depth=1 --branch=v5.14 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git linux
 	cd linux
 
 	if [[ "${BUILD_ARCH}" = "x86-64" ]]; then