Merge pull request #9891 from mitake/maintainers

MAINTAINERS: update @mitake's email address

MAINTAINERS

@@ -10,7 +10,7 @@ Anthony Romano <romanoanthony061@gmail.com> (@heyitsanthony) pkg:*
 Brandon Philips <bphilips@redhat.com> (@philips) pkg:*
 Fanmin Shi <fashi@redhat.com> (@fanminshi) pkg:*
 Gyuho Lee <gyuhox@gmail.com> <gylee@redhat.com> (@gyuho) pkg:*
-Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp> (@mitake) pkg:*
+Hitoshi Mitake <h.mitake@gmail.com> (@mitake) pkg:*
 Xiang Li <xiangli.cs@gmail.com> (@xiang90) pkg:*
 
 Ben Darnell <ben@cockroachlabs.com> (@bdarnell) pkg:github.com/coreos/etcd/raft