MAINTAINERS: update KVM/s390 maintainers

As I have neither too much time nor access to the architecture
documentation anymore, let's switch my status from maintainer to
reviewer. Janosch will step in as second maintainer.

Acked-by: Janosch Frank <[email protected]>
Acked-by: Christian Borntraeger <[email protected]>
Signed-off-by: Cornelia Huck <[email protected]>

MAINTAINERS

@@ -7692,8 +7692,9 @@ F:	arch/powerpc/kernel/kvm*
 
 KERNEL VIRTUAL MACHINE for s390 (KVM/s390)
 M:	Christian Borntraeger <[email protected]>
-M:	Cornelia Huck <cohuck@redhat.com>
+M:	Janosch Frank <[email protected].com>
 R:	David Hildenbrand <[email protected]>
+R:	Cornelia Huck <[email protected]>
 L:	[email protected]
 W:	http://www.ibm.com/developerworks/linux/linux390/
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git