rtc: fix platform driver hotplug/coldplug

Since 43cc71eed1250755986da4c0f9898f9a635cb3bf, the platform modalias is
prefixed with "platform:".  Add MODULE_ALIAS() to the hotpluggable RTC
platform drivers, to re-enable module auto loading.

[dbrownell@users.sourceforge.net: more drivers, minor fix]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <greg@kroah.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-vr41xx.c b/drivers/rtc/rtc-vr41xx.c
index ce2f78d..be9c70d 100644
--- a/drivers/rtc/rtc-vr41xx.c
+++ b/drivers/rtc/rtc-vr41xx.c
@@ -422,6 +422,9 @@
 	return 0;
 }
 
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:RTC");
+
 static struct platform_driver rtc_platform_driver = {
 	.probe		= rtc_probe,
 	.remove		= __devexit_p(rtc_remove),