MAINTAINERS: Add serial

Add an entry for serial maintainers.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS

@@ -5409,6 +5409,12 @@ L:	alsa-devel@alsa-project.org (moderated for non-subscribers)
 S:	Supported
 F:	sound/soc/samsung
 
+SERIAL DRIVERS
+M:	Alan Cox <alan@linux.intel.com>
+L:	linux-serial@vger.kernel.org
+S:	Maintained
+F:	drivers/tty/serial
+
 TIMEKEEPING, NTP
 M:	John Stultz <johnstul@us.ibm.com>
 M:	Thomas Gleixner <tglx@linutronix.de>