COMPMID-3689: Update function list in doxygen

- NE/CLMaxUnpoolingLayer have been added to the function list.
- Missing documentation for deprecated interface has been added
  to the release note.

Change-Id: I1bd5f37a15545ffc714a9fa7a0d56738d4744fd3
Signed-off-by: Sang-Hoon Park <sang-hoon.park@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/3785
Reviewed-by: Sheri Zhang <sheri.zhang@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
diff --git a/docs/06_functions_list.dox b/docs/06_functions_list.dox
index 99eab12..ac94461 100644
--- a/docs/06_functions_list.dox
+++ b/docs/06_functions_list.dox
@@ -159,6 +159,7 @@
     - @ref NELSTMLayer
     - @ref NELSTMLayerQuantized
     - @ref NEQLSTMLayer
+    - @ref NEMaxUnpoolingLayer
     - @ref NEMeanStdDev
     - @ref NEMinMaxLocation
     - @ref NENormalizationLayer
@@ -233,6 +234,7 @@
     - @ref CLLSTMLayer
     - @ref CLLSTMLayerQuantized
     - @ref CLQLSTMLayer
+    - @ref CLMaxUnpoolingLayer
     - @ref CLMeanStdDev
     - @ref CLMinMaxLocation
     - @ref CLNormalizationLayer