MAINTAINERS: add myself as arm64/xen maintainer

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

MAINTAINERS

@@ -9096,6 +9096,13 @@ S:	Supported
 F:	arch/arm/xen/
 F:	arch/arm/include/asm/xen/
 
+XEN HYPERVISOR ARM64
+M:	Stefano Stabellini <stefano.stabellini@eu.citrix.com>
+L:	xen-devel@lists.xensource.com (moderated for non-subscribers)
+S:	Supported
+F:	arch/arm64/xen/
+F:	arch/arm64/include/asm/xen/
+
 XEN NETWORK BACKEND DRIVER
 M:	Ian Campbell <ian.campbell@citrix.com>
 L:	xen-devel@lists.xensource.com (moderated for non-subscribers)