Document changes and release 5.13.1pureos1~amber1 of linux-next-librem5

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
2 jobs for pureos/5.13.1pureos1_amber1 in 68 minutes and 18 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
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passed #359068
librem5
build:aarch64

00:38:25

passed #359069
librem5:arm64
build:deb

01:08:18