MAINTAINERS: Add iuliana-prodan as Open AMP maintainer

Move myself from collaborators to maintainers.

Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>

Author: iuliana-prodan

MAINTAINERS.yml

@@ -3284,9 +3284,9 @@ Open AMP:
   status: maintained
   maintainers:
     - carlocaione
+    - iuliana-prodan
   collaborators:
     - uLipe
-    - iuliana-prodan
   files:
     - lib/open-amp/
     - samples/subsys/ipc/openamp/