powerpc: don't use module_init in non-modular 83xx suspend code

The suspend.o is built for SUSPEND -- 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: Scott Wood <scottwood@freescale.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

arch/powerpc/platforms/83xx/suspend.c

@@ -445,5 +445,4 @@ static int pmc_init(void)
 {
 	return platform_driver_register(&pmc_driver);
 }
-
-module_init(pmc_init);
+device_initcall(pmc_init);