MAINTAINERS: GNSS: Add collaborators

Add tomi-font and fabiobaltieri as collaborators of the
"Drivers: GNSS" area

Signed-off-by: Bjarki Arge Andreasen <bjarki@arge-andreasen.me>

Author: bjarki-andreasen

MAINTAINERS.yml

@@ -1323,6 +1323,9 @@ Release Notes:
   status: maintained
   maintainers:
     - bjarki-trackunit
+  collaborators:
+    - tomi-font
+    - fabiobaltieri
   files:
     - doc/hardware/peripherals/gnss.rst
     - drivers/gnss/