MAINTAINERS: update Allwinner A10 maintainer

Change the maintainer for Allwinner A10 to myself as Li Guang's mail
address bounces. While at it, extend the file pattern for the entry to
include allwinner_emac.[ch].

Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-id: 1442865156-5598-1-git-send-email-b.galvani@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

MAINTAINERS

@@ -266,10 +266,10 @@ F: *win32*
 ARM Machines
 ------------
 Allwinner-a10
-M: Li Guang <lig.fnst@cn.fujitsu.com>
+M: Beniamino Galvani <b.galvani@gmail.com>
 S: Maintained
-F: hw/*/allwinner-a10*
-F: include/hw/*/allwinner-a10*
+F: hw/*/allwinner*
+F: include/hw/*/allwinner*
 F: hw/arm/cubieboard.c
 
 Exynos