EDAC: Make device_type const

Make these const as they are only stored in the type field of a device
structure, which is const.

Done using Coccinelle.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1503130946-2854-2-git-send-email-bhumirks@gmail.com


Signed-off-by: Borislav Petkov <bp@suse.de>