MAINTAINERS: move TF-A to non-maintained

Former maintainers povergoing and sgrrzhf have not been active for several
releases despite attempts to contact them. Instead of keeping PRs and
releases gating on having them respond remove them from the maintainers
list until they can return.

Unfortunately this moves TF-A from maintained to odd fixes.

Signed-off-by: Dan Kalowsky <[email protected]>

Author: dkalowsk

MAINTAINERS.yml

@@ -6100,10 +6100,7 @@ West:
     - thrift
 
 "West project: trusted-firmware-a":
-  status: maintained
-  maintainers:
-    - povergoing
-    - sgrrzhf
+  status: odd fixes
   collaborators:
     - wearyzen
     - ithinuel