MAINTAINERS: reciprocal co-maintainership for file locking and nfsd

Chuck has agreed to backstop me as maintainer of the file locking code,
and I'll do the same for him on knfsd.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Author: jtlayton

MAINTAINERS

@@ -7572,6 +7572,7 @@ F:	include/uapi/scsi/fc/
 
 FILE LOCKING (flock() and fcntl()/lockf())
 M:	Jeff Layton <jlayton@kernel.org>
+M:	Chuck Lever <chuck.lever@oracle.com>
 L:	linux-fsdevel@vger.kernel.org
 S:	Maintained
 F:	fs/fcntl.c
@@ -10646,6 +10647,7 @@ W:	http://kernelnewbies.org/KernelJanitors
 
 KERNEL NFSD, SUNRPC, AND LOCKD SERVERS
 M:	Chuck Lever <chuck.lever@oracle.com>
+M:	Jeff Layton <jlayton@kernel.org>
 L:	linux-nfs@vger.kernel.org
 S:	Supported
 W:	http://nfs.sourceforge.net/