MAINTAINERS: socfpga: update email address for Dinh Nguyen

With the acquisition of Altera by Intel, my Altera email may be going
away soon. Update the contact to a more reliable address.

Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
diff --git a/board/altera/arria5-socdk/MAINTAINERS b/board/altera/arria5-socdk/MAINTAINERS
index ba35b36..873ec2b 100644
--- a/board/altera/arria5-socdk/MAINTAINERS
+++ b/board/altera/arria5-socdk/MAINTAINERS
@@ -1,5 +1,5 @@
 SOCFPGA BOARD
-M:	Dinh Nguyen <dinguyen@opensource.altera.com>
+M:	Dinh Nguyen <dinguyen@kernel.org>
 M:	Chin-Liang See <clsee@altera.com>
 S:	Maintained
 F:	board/altera/arria5-socdk/