MAINTAINERS: Add entry for NXP LPC18xx/43xx MCUs

Add a MAINTAINER entry covering all NXP LPC18xx/43xx
machine and drivers files.
Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

MAINTAINERS

@@ -1189,6 +1189,12 @@ M:	Lennert Buytenhek <kernel@wantstofly.org>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 
+ARM/LPC18XX ARCHITECTURE
+M:	Joachim Eastwood <manabian@gmail.com>
+L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
+S:	Maintained
+N:	lpc18xx
+
 ARM/MAGICIAN MACHINE SUPPORT
 M:	Philipp Zabel <philipp.zabel@gmail.com>
 S:	Maintained