Document changes and release 5.12.2pureos4~amber1 of linux-librem5

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
2 jobs for pureos/5.12.2pureos4_amber1 in 64 minutes and 22 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
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passed #353792
librem5
build:aarch64

00:19:48

passed #353793
librem5:arm64
build:deb

01:04:21