ARM: S3C64XX: mach-crag6410-module.c is not modular

Despite the name mach-crag6410-module.c, the code is built for
MACH_WLF_CRAGG_6410 -- which is bool, and hence this code is
either present or absent.  It will never be modular, so using
module_init as an alias for __initcall can be somewhat
misleading.

Fix this up now, so that we can relocate module_init from
init.h into module.h in the future.  If we don't do this, we'd
have to add module.h to obviously non-modular code, and that
would be a worse thing.

Note that direct use of __initcall is discouraged, vs. one
of the priority categorized subgroups.  As __initcall gets
mapped onto device_initcall, our use of device_initcall
directly in this change means that the runtime impact is
zero -- it will remain at level 6 in initcall ordering.

Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: patches@opensource.wolfsonmicro.com
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>