MAINTAINERS: add lib/raid6/ to "SOFTWARE RAID"

Cc: Song Liu <[email protected]>
Cc: Yu Kuai <[email protected]>
Cc: Herbert Xu <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: akpm00

MAINTAINERS

@@ -23053,6 +23053,7 @@ F:	drivers/md/md*
 F:	drivers/md/raid*
 F:	include/linux/raid/
 F:	include/uapi/linux/raid/
+F:	lib/raid6/
 
 SOLIDRUN CLEARFOG SUPPORT
 M:	Russell King <[email protected]>