Documentation: Add MCB documentation

Add basic introductory documentation for the MEN Chameleon Bus.

Signed-off-by: Johannes Thumshirn <[email protected]>
Signed-off-by: Jonathan Corbet <[email protected]>
diff --git a/MAINTAINERS b/MAINTAINERS
index 8133cef..b9b9156 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6665,6 +6665,7 @@
 S:	Maintained
 F:	drivers/mcb/
 F:	include/linux/mcb.h
+F:	Documentation/men-chameleon-bus.txt
 
 MEN F21BMC (Board Management Controller)
 M:	Andreas Werner <[email protected]>