MAINTAINERS: Add nios2 maintainer

Signed-off-by: Ley Foon Tan <lftan@altera.com>

MAINTAINERS

@@ -6561,6 +6561,13 @@ S:	Maintained
 F:	Documentation/scsi/NinjaSCSI.txt
 F:	drivers/scsi/nsp32*
 
+NIOS2 ARCHITECTURE
+M:	Ley Foon Tan <lftan@altera.com>
+L:	nios2-dev@lists.rocketboards.org (moderated for non-subscribers)
+T:	git git://git.rocketboards.org/linux-socfpga.git
+S:	Maintained
+F:	arch/nios2/
+
 NTB DRIVER
 M:	Jon Mason <jdmason@kudzu.us>
 M:	Dave Jiang <dave.jiang@intel.com>