MAINTAINERS: RCU now has its own email list

This commit makes rcu@vger.kernel.org be the official list for RCU-related
topics.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>

MAINTAINERS

@@ -13031,7 +13031,7 @@ M:	Josh Triplett <josh@joshtriplett.org>
 R:	Steven Rostedt <rostedt@goodmis.org>
 R:	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 R:	Lai Jiangshan <jiangshanlai@gmail.com>
-L:	linux-kernel@vger.kernel.org
+L:	rcu@vger.kernel.org
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
 F:	tools/testing/selftests/rcutorture
@@ -13079,7 +13079,7 @@ R:	Steven Rostedt <rostedt@goodmis.org>
 R:	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 R:	Lai Jiangshan <jiangshanlai@gmail.com>
 R:	Joel Fernandes <joel@joelfernandes.org>
-L:	linux-kernel@vger.kernel.org
+L:	rcu@vger.kernel.org
 W:	http://www.rdrop.com/users/paulmck/RCU/
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
@@ -14234,7 +14234,7 @@ M:	"Paul E. McKenney" <paulmck@linux.ibm.com>
 M:	Josh Triplett <josh@joshtriplett.org>
 R:	Steven Rostedt <rostedt@goodmis.org>
 R:	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
-L:	linux-kernel@vger.kernel.org
+L:	rcu@vger.kernel.org
 W:	http://www.rdrop.com/users/paulmck/RCU/
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git