Remove myself as MD Maintainer, and add to Credits.

Signed-off-by: NeilBrown <neilb@suse.com>
diff --git a/CREDITS b/CREDITS
index 8207cc6..fd934f0 100644
--- a/CREDITS
+++ b/CREDITS
@@ -534,6 +534,7 @@
 E: neil@brown.name
 P: 4096R/566281B9 1BC6 29EB D390 D870 7B5F  497A 39EC 9EDD 5662 81B9
 D: NFSD Maintainer 2000-2007
+D: MD Maintainer 2001-2016
 
 N: Zach Brown
 E: zab@zabbo.net