MAINTAINERS: Add Magnus Lindholm as maintainer for alpha port

Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Acked-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

Author: linmag7

MAINTAINERS

@@ -915,6 +915,7 @@ F:	drivers/staging/media/sunxi/cedrus/
 ALPHA PORT
 M:	Richard Henderson <richard.henderson@linaro.org>
 M:	Matt Turner <mattst88@gmail.com>
+M:	Magnus Lindholm <linmag7@gmail.com>
 L:	linux-alpha@vger.kernel.org
 S:	Odd Fixes
 F:	arch/alpha/