MAINTAINERS: Update Avi Kivity's email address

Signed-off-by: Avi Kivity <avi@redhat.com>

MAINTAINERS

@@ -2443,7 +2443,7 @@ S:	Supported
 
 KERNEL VIRTUAL MACHINE (KVM)
 P:	Avi Kivity
-M:	avi@qumranet.com
+M:	avi@redhat.com
 L:	kvm@vger.kernel.org
 W:	http://kvm.qumranet.com
 S:	Supported