Document changes and release 5.13.16pureos1~amber1 of linux-librem5

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
2 jobs for release51316_1_amber in 78 minutes and 18 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
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passed #367313
librem5
build:aarch64

00:47:35

passed #367314
librem5:arm64
build:deb

01:10:00