KVM: taking co-maintenance

Updating MAINTAINERS file.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

MAINTAINERS

@@ -4281,6 +4281,7 @@ F:	include/linux/sunrpc/
 
 KERNEL VIRTUAL MACHINE (KVM)
 M:	Marcelo Tosatti <mtosatti@redhat.com>
+M:	Gleb Natapov <gleb@redhat.com>
 L:	kvm@vger.kernel.org
 W:	http://kvm.qumranet.com
 S:	Supported