doc: correct references to overlay-fdt-boot.txt
doc/uImage.FIT/overlay-fdt-boot.txt does not exist anymore.
Reference the correct section of doc/usage/fit/overlay-fdt-boot.rst.
Fixes: 6f6e8bb695a7 ("doc: Bring in the FIT overlay information")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/doc/usage/fit/overlay-fdt-boot.rst b/doc/usage/fit/overlay-fdt-boot.rst
index a7db1a3..3d7296a 100644
--- a/doc/usage/fit/overlay-fdt-boot.rst
+++ b/doc/usage/fit/overlay-fdt-boot.rst
@@ -111,6 +111,8 @@
This selects the DTB to use when booting.
+.. _fit_configuration_using_overlays:
+
Configuration using overlays
----------------------------