codeowners: Add Lyndeno for XPS-9560

This is my daily driver and I foresee this to be the case for a long
while.

Contributions directly to this model:
- #691
- #696

Contributions indirectly affecting this model:
- #692

CODEOWNERS

@@ -1,6 +1,7 @@
 beagleboard/pocketbeagle @yegortimoshenko
 dell/xps/13-9370 @moredread
 dell/xps/13-9380 @kalbasit
+dell/xps/15-9560 @Lyndeno
 lenovo/thinkpad/x230 @makefu @yegortimoshenko
 lenovo/thinkpad/x250 @Mic92
 pcengines/apu @yegortimoshenko