doc: release-notes: add doc changes
Add relevant documentation changes.
@@ -883,6 +883,9 @@ https://github.com/zephyrproject-rtos/zcbor/blob/0.6.0/RELEASE_NOTES.md
Documentation
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+* Upgraded to Doxygen 1.9.6.
+* It is now possible to link to Kconfig search results.
+
Tests and Samples
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