MAINTAINERS: Update mail address for COLO Proxy

My Fujitsu mail account will be disabled soon, update the mail info
to my private mail.

Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

MAINTAINERS

@@ -1577,7 +1577,7 @@ F: include/migration/failover.h
 F: docs/COLO-FT.txt
 
 COLO Proxy
-M: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
+M: Zhang Chen <zhangckid@gmail.com>
 M: Li Zhijian <lizhijian@cn.fujitsu.com>
 S: Supported
 F: docs/colo-proxy.txt