MAINTAINERS: Update s390/cio maintainer

Update maintainer entry for s390 Common I/O Layer.
Sebastian has left IBM, Vineeth takes over maintainership.
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Acked-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

MAINTAINERS

@@ -14461,7 +14461,7 @@ F:	Documentation/s390/
 F:	Documentation/driver-api/s390-drivers.rst
 
 S390 COMMON I/O LAYER
-M:	Sebastian Ott <sebott@linux.ibm.com>
+M:	Vineeth Vijayan <vneethv@linux.ibm.com>
 M:	Peter Oberparleiter <oberpar@linux.ibm.com>
 L:	linux-s390@vger.kernel.org
 W:	http://www.ibm.com/developerworks/linux/linux390/