MAINTAINERS: s390x: remove myself as maintainer

kvm-unit-tests for s390x is nowadays in a pretty good shape and in even
better hands. As I've been mostly only reviewing selected patches
lately because other projects are more important, and Thomas and Janosch
have been handling PULL requests for a long time now without me, remove
myself as maintainer.

But I want to know what's happening, so keep me added as a reviewer --
so I can continue reviewing selected patches :)

Signed-off-by: David Hildenbrand <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Thomas Huth <[email protected]>

Author: davidhildenbrand

MAINTAINERS

@@ -82,10 +82,10 @@ F: lib/ppc64/*
 
 S390X
 M: Thomas Huth <[email protected]>
-M: David Hildenbrand <[email protected]>
 M: Janosch Frank <[email protected]>
 R: Cornelia Huck <[email protected]>
 R: Claudio Imbrenda <[email protected]>
+R: David Hildenbrand <[email protected]>
 L: [email protected]
 L: [email protected]
 F: s390x/*