Document changes and release 5.11.1pureos1 of linux-next-librem5

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>

debian/changelog

+linux-next-librem5 (5.11.1pureos1) byzantium; urgency=medium
+
+  [ Dorota Czaplejewicz ]
+  * s5k3l6xx updates
+
+  [ Martin Kepplinger ]
+  * rebase the l5 tree onto v5.11.1
+  * hi846 / csi updates
+
+  [ Guido Günther ]
+  * add rfkill-hks platform driver
+
+ -- Martin Kepplinger <martin.kepplinger@puri.sm>  Wed, 24 Feb 2021 11:27:29 +0100
+
 linux-next-librem5 (5.11.0pureos1) byzantium; urgency=medium
 
   [ Dorota Czaplejewicz ]