doc: releases: add ili9xxx fixes to 4.4 releases notes & migration guide

Added documentation for doc/releases/migration-guide-4.4.rst
in reference with the changes on ili9xxx and ili9341
controllers

Signed-off-by: Nicolas Moreno <[email protected]>

Author: NickIOT72

doc/releases/migration-guide-4.4.rst

@@ -32,6 +32,15 @@ Boards
 Device Drivers and Devicetree
 *****************************
 
+Display
+=======
+
+* For ILI9XXX controllers, the usage of ``ILI9XXX_PIXEL_FORMAT_x`` in devicetrees for panel color format selection
+  has been updated to ``PANEL_PIXEL_FORMAT_x``. Out-of-tree boards and shields should be updated accordingly.
+  (:github:`99267`).
+* For ILI9341 controller, display mirroring configuration has been updated to conform with the described behavior
+  of the sample ``samples/drivers/display``. (:github:`99267`).
+
 QSPI
 ===