alpha: add myself as a maintainer, and drop mention of 2.4

CC: Richard Henderson <rth@twiddle.net>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
CC: linux-alpha@vger.kernel.org
Signed-off-by: Matt Turner <mattst88@gmail.com>

MAINTAINERS

@@ -410,9 +410,8 @@ F:	drivers/i2c/busses/i2c-ali1563.c
 
 ALPHA PORT
 M:	Richard Henderson <rth@twiddle.net>
-S:	Odd Fixes for 2.4; Maintained for 2.6.
 M:	Ivan Kokshaysky <ink@jurassic.park.msu.ru>
-S:	Maintained for 2.4; PCI support for 2.6.
+M:	Matt Turner <mattst88@gmail.com>
 L:	linux-alpha@vger.kernel.org
 F:	arch/alpha/