m68k/mvme16x: rtc - Don't use module_init in non-modular code

The rtc.o is built for obj-y, i.e. always built in.  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.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

arch/m68k/mvme16x/rtc.c

@@ -161,4 +161,4 @@ static int __init rtc_MK48T08_init(void)
 	printk(KERN_INFO "MK48T08 Real Time Clock Driver v%s\n", RTC_VERSION);
 	return misc_register(&rtc_dev);
 }
-module_init(rtc_MK48T08_init);
+device_initcall(rtc_MK48T08_init);