ARM i.MX27 pm: return gracefully on different socs

Code called from an initcall can be maybe called for
machines it's not intended for. So check for valid
machines and return gracefully if an incompatible machine
is found.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/mach-imx/pm-imx27.c

@@ -39,6 +39,9 @@ static struct platform_suspend_ops mx27_suspend_ops = {
 
 static int __init mx27_pm_init(void)
 {
+	if (!cpu_is_mx27())
+		return 0;
+
 	suspend_set_ops(&mx27_suspend_ops);
 	return 0;
 }