docs(changelog): changelog for lts-v2.8.11 release

Generated with the command:
npm run release -- --release-as 2.8.11

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: I5fc96f3a21bfa0b2d450b37ab1425f9d8f4d441c
diff --git a/Makefile b/Makefile
index ef383f7..8ee345d 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@
 #
 VERSION_MAJOR			:= 2
 VERSION_MINOR			:= 8
-VERSION_PATCH			:= 10
+VERSION_PATCH			:= 11
 VERSION				:= ${VERSION_MAJOR}.${VERSION_MINOR}.${VERSION_PATCH}
 
 # Default goal is build all images