MAINTAINERS: change mhocko's email address to kernel.org

I am moving from mhocko@suse.cz to mhocko@kernel.org for kernel related
stuff.
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS

@@ -2864,7 +2864,7 @@ F:	kernel/cpuset.c
 
 CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)
 M:	Johannes Weiner <hannes@cmpxchg.org>
-M:	Michal Hocko <mhocko@suse.cz>
+M:	Michal Hocko <mhocko@kernel.org>
 L:	cgroups@vger.kernel.org
 L:	linux-mm@kvack.org
 S:	Maintained