Support for RCM4 with A311D Processor, Kernel 6.5 (v2)

See merge request !13

dpkg 1.22.0 started adding -mbranch-protection=standard on arm64. This
breaks cross builds for arm64 which add CFLAGS to CC_FOR_BUILD
invocations as well because CFLAGS are assembled for the host
architecture and might break build architecture compiler invocations.

linux: backport some etnaviv changes

See merge request !11

These two patches will be 6.6 material but it makes sense to backport
them. The first patch will reduce FE idle memory traffic to 512 KB/s.
The second patch makes devcoredumps from etnaviv more reliable.

Signed-off-by: Christian Gmeiner <cgmeiner@igalia.com>

Linux 6.4, A311D support

See merge request !9

linux/build.sh: re-enable copying pocket reform dts (disabled in 'initial support for meson-g12b-bananapi-cm4-mnt-reform2')

.gitlab-ci.yml: install debian-archive-keyring because symlink chdist/base/etc/apt/trusted.gpg.d/debian-archive-keyring.gpg points to it

linux/patches/imx8mq-mnt-reform2/0005-imx8mq-import-HDMI-driver-and-make-DCSS-compatible-w.patch: move cdn-mhdp stuff into cdns subdirectory

split build job into parallel jobs

See merge request !8