docs(changelog): changelog for lts-v2.8.8 release

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: I07a96ddab3c846bc3d729a425f88b0ef56bf7fbb
diff --git a/Makefile b/Makefile
index 3aa8bb8..ba47db4 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@
 #
 VERSION_MAJOR			:= 2
 VERSION_MINOR			:= 8
-VERSION_PATCH			:= 7
+VERSION_PATCH			:= 8
 VERSION				:= ${VERSION_MAJOR}.${VERSION_MINOR}.${VERSION_PATCH}
 
 # Default goal is build all images